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CAT 2024 DILR Questions — Slot 3

The actual Data Interpretation & Logical Reasoning section from CAT 2024, Slot 3 — 22 questions in original paper order, each with a full worked solution. Tap an option (or type your answer) to check yourself before reading the solution.

22 questions12 MCQ · 10 TITA40 min section0/22 attempted
Set · Data Tables

Out of 10 countries -- Country 1 through Country 10 -- Country 9 has the highest gross domestic product (GDP), and Country 10 has the highest GDP per capita. GDP per capita is the GDP of a country divided by its population. The table below provides the following data about Country 1 through Country 8 for the year 2024. Column 1 gives the country's identity. Column 2 gives the country's GDP as a fraction of the GDP of Country 9. Column 3 gives the country's GDP per capita as a fraction of the GDP per capita of Country 10. Column 4 gives the country's annual GDP growth rate. Column 5 gives the country's annual population growth rate. Assume that the GDP growth rates and population growth rates of the countries will remain constant for the next three years.

Table: Data for Country 1 through Country 8 for the year 2024. Column 2 = GDP as a fraction of Country 9's GDP; Column 3 = GDP per capita as a fraction of Country 10's GDP per capita; Column 4 = annual GDP growth rate; Column 5 = annual population growth rate.

CountryGDP (frac of C9)GDP per capita (frac of C10)GDP growth ratePopulation growth rate
Country 10.150.410.2%-0.12%
Country 20.140.250.9%-0.41%
Country 30.130.026.5%0.70%
Country 40.120.380.5%0.49%
Country 50.100.360.7%0.31%
Country 60.080.083.2%0.61%
Country 70.080.300.7%-0.11%
Country 80.070.411.2%0.71%
Q1Data TablesMCQ

Which one among the countries 1 through 8, has the smallest population in 2024?

Show solution

Correct answer: A

Finding the smallest population in 2024

The key relationship given in the set-up is:

GDP per capita=GDPPopulation\text{GDP per capita} = \frac{\text{GDP}}{\text{Population}}

Rearranging this:

Population=GDPGDP per capita\text{Population} = \frac{\text{GDP}}{\text{GDP per capita}}

The table gives each country's GDP as a fraction of Country 9's GDP, and its GDP per capita as a fraction of Country 10's GDP per capita. Since both columns use the same reference country across all rows, dividing Column 2 by Column 3 gives each country's population relative to a common baseline. We don't need absolute numbers — we only need to compare these ratios.

CountryGDP (frac of C9)GDPpc (frac of C10)Relative population = GDP ÷ GDPpc
Country 10.150.410.15 / 0.41 = 0.366
Country 20.140.250.14 / 0.25 = 0.560
Country 30.130.020.13 / 0.02 = 6.500
Country 40.120.380.12 / 0.38 = 0.316
Country 50.100.360.10 / 0.36 = 0.278
Country 60.080.080.08 / 0.08 = 1.000
Country 70.080.300.08 / 0.30 = 0.267
Country 80.070.410.07 / 0.41 = 0.171

💡 Teacher tip: You never need the actual GDP of Country 9 or the actual GDP per capita of Country 10. Because every row is expressed against the same reference, the ratio (Column 2 ÷ Column 3) preserves the correct ordering of populations.

Scanning the last column, the smallest value is 0.171, which belongs to Country 8.

Answer: A. Country 8

Q2Data TablesMCQ

The ratio of Country 4's GDP to Country 5's GDP in 2026 will be closest to

Show solution

Correct answer: A

Ratio of Country 4's GDP to Country 5's GDP in 2026

We need the GDP ratio two years after 2024 (i.e., in 2026). Each country's GDP grows at its own annual GDP growth rate, compounded yearly.

From the table:

CountryGDP in 2024 (frac of C9)Annual GDP growth rate
Country 40.120.5%
Country 50.100.7%

After 2 years of compounding:

GDPC4(2026)=0.12×(1.005)2\text{GDP}_{C4}(2026) = 0.12 \times (1.005)^2

GDPC5(2026)=0.10×(1.007)2\text{GDP}_{C5}(2026) = 0.10 \times (1.007)^2

The required ratio is:

GDPC4(2026)GDPC5(2026)=0.12×(1.005)20.10×(1.007)2=0.120.10×(1.0051.007)2\frac{\text{GDP}_{C4}(2026)}{\text{GDP}_{C5}(2026)} = \frac{0.12 \times (1.005)^2}{0.10 \times (1.007)^2} = \frac{0.12}{0.10} \times \left(\frac{1.005}{1.007}\right)^2

Computing each piece:

  • 0.120.10=1.2\frac{0.12}{0.10} = 1.2
  • (1.005)2=1.010025(1.005)^2 = 1.010025
  • (1.007)2=1.014049(1.007)^2 = 1.014049

Ratio=1.2×1.0100251.014049=1.2×0.99603≈1.195\text{Ratio} = 1.2 \times \frac{1.010025}{1.014049} = 1.2 \times 0.99603 \approx 1.195

💡 Teacher tip: The population growth rate is irrelevant here — the question asks only about GDP, which depends solely on the GDP growth rate. Don't let the extra column distract you.

Answer: A. 1.195

Q3Data TablesMCQ

Which one among the countries 1, 4, 5, and 7 will have the largest population in 2027?

Show solution

Correct answer: A

Largest population in 2027 among Countries 1, 4, 5, and 7

Step 1 — Find each country's relative population in 2024.

Since Population=GDP÷GDP per capita\text{Population} = \text{GDP} \div \text{GDP per capita}, we divide Column 2 by Column 3:

CountryGDP (frac of C9)GDPpc (frac of C10)Relative pop. (2024)Pop. growth rate
Country 10.150.410.366−0.12%
Country 40.120.380.316+0.49%
Country 50.100.360.278+0.31%
Country 70.080.300.267−0.11%

Step 2 — Project each population forward 3 years (2024 → 2027).

Each population is multiplied by (1+r)3(1 + r)^3 where rr is the population growth rate.

  • Country 1: 0.366×(0.9988)3≈0.366×0.9964≈0.3650.366 \times (0.9988)^3 \approx 0.366 \times 0.9964 \approx 0.365
  • Country 4: 0.316×(1.0049)3≈0.316×1.0148≈0.3210.316 \times (1.0049)^3 \approx 0.316 \times 1.0148 \approx 0.321
  • Country 5: 0.278×(1.0031)3≈0.278×1.0093≈0.2810.278 \times (1.0031)^3 \approx 0.278 \times 1.0093 \approx 0.281
  • Country 7: 0.267×(0.9989)3≈0.267×0.9967≈0.2660.267 \times (0.9989)^3 \approx 0.267 \times 0.9967 \approx 0.266
Country2024 relative pop.2027 relative pop. (approx.)
Country 10.3660.365
Country 40.3160.321
Country 50.2780.281
Country 70.2670.266

💡 Teacher tip: Country 4 has the highest population growth rate among the four, so it closes the gap slightly — but the starting gap between Country 1 (0.366) and Country 4 (0.316) is far too large to close in just three years at these small rates. Country 1 stays on top.

Even after three years of growth, Country 1 remains the most populous.

Answer: A. Country 1

Q4Data TablesTITA

For how many countries among Country 1 through Country 8 will the GDP per capita in 2027 be lower than that in 2024?

Show solution

Correct answer: 0

Counting countries whose GDP per capita falls by 2027

Key idea: GDP per capita =GDP÷Population= \text{GDP} \div \text{Population}. Over time, GDP grows at the GDP growth rate and population grows at the population growth rate. So the annual growth rate of GDP per capita is approximately:

GDP per capita growth rate≈(GDP growth rate)−(Population growth rate)\text{GDP per capita growth rate} \approx (\text{GDP growth rate}) - (\text{Population growth rate})

If this difference is positive, GDP per capita rises over the three years. If it is negative, GDP per capita falls.

Step 1 — Compute the difference for every country.

CountryGDP growth ratePopulation growth rateDifference (GDP gr − Pop gr)
Country 10.2%−0.12%0.2 − (−0.12) = +0.32%
Country 20.9%−0.41%0.9 − (−0.41) = +1.31%
Country 36.5%0.70%6.5 − 0.70 = +5.80%
Country 40.5%0.49%0.5 − 0.49 = +0.01%
Country 50.7%0.31%0.7 − 0.31 = +0.39%
Country 63.2%0.61%3.2 − 0.61 = +2.59%
Country 70.7%−0.11%0.7 − (−0.11) = +0.81%
Country 81.2%0.71%1.2 − 0.71 = +0.49%

💡 Teacher tip: Watch the signs carefully. Countries 1, 2, and 7 have negative population growth rates (their populations are shrinking). Subtracting a negative number adds, which makes the GDP-per-capita growth even larger. Country 4 is the closest call — GDP grows only 0.01% faster than population — but it is still positive, so GDP per capita still rises (barely).

Step 2 — Count the countries where GDP per capita falls.

Every single difference is positive, meaning GDP per capita increases for all eight countries from 2024 to 2027. Therefore, the number of countries whose GDP per capita in 2027 is lower than in 2024 is:

0\boxed{0}

Answer: 0

Set · Mixed Charts & Caselets

Over the top (OTT) subscribers of a platform are segregated into three categories: i) Kid, ii) Elder, and iii) Others. Some of the subscribers used one app and the others used multiple apps to access the platform. The figure below shows the percentage of the total number of subscribers in 2023 and 2024 who belong to the 'Kid' and 'Elder' categories. The following additional facts are known about the numbers of subscribers. 1. The total number of subscribers increased by 10% from 2023 to 2024. 2. In 2024, 1/2 of the subscribers from the 'Kid' category and 2/3 of the subscribers from the 'Elder' category subscribers use one app. 3. In 2023, the number of subscribers from the 'Kid' category who used multiple apps was the same as the number of subscribers from the 'Elder' category who used one app. 4. 10,000 subscribers from the 'Kid' category used one app and 15,000 subscribers from the 'Elder' category used multiple apps in 2023.

Bar chart: Percentage of total subscribers belonging to the 'Kid' and 'Elder' categories in 2023 and 2024.

Category20232024
Kid15%20%
Elder20%30%
Q5Mixed Charts & CaseletsMCQ

How many subscribers belonged to the 'Others' category in 2024?

Show solution

Correct answer: C

Finding the total number of subscribers

Let TT be the total number of subscribers in 2023. Since the total grew by 10% (clue 1), the 2024 total is 1.1T1.1T.

From the bar chart:

Category20232024
Kid0.15T0.15T0.20×1.1T=0.22T0.20 \times 1.1T = 0.22T
Elder0.20T0.20T0.30×1.1T=0.33T0.30 \times 1.1T = 0.33T
Others0.65T0.65T0.50×1.1T=0.55T0.50 \times 1.1T = 0.55T

We need TT to get actual numbers. Use clues 3 and 4.

Clue 4 tells us that in 2023:

  • Kid one-app = 10,000
  • Elder multi-app = 15,000

Clue 3 says: Kid-multi (2023) = Elder-one-app (2023). Let this common value be xx.

So in 2023:

  • Kid total = 10,000+x=0.15T10{,}000 + x = 0.15T
  • Elder total = x+15,000=0.20Tx + 15{,}000 = 0.20T

From the Elder equation: x=0.20T−15,000x = 0.20T - 15{,}000.

Substitute into the Kid equation: 10,000+0.20T−15,000=0.15T10{,}000 + 0.20T - 15{,}000 = 0.15T 0.05T=5,0000.05T = 5{,}000 T=100,000\boxed{T = 100{,}000}

So the 2024 total = 1.1×100,000=110,0001.1 \times 100{,}000 = 110{,}000.

Answering the question

In 2024, Others = 50% of the total: 0.50×110,000=55,0000.50 \times 110{,}000 = 55{,}000

Answer: C. 55,000

Q6Mixed Charts & CaseletsMCQ

What percentage of subscribers in the 'Kid' category used multiple apps in 2023?

Show solution

Correct answer: A

Setting up the numbers

Let TT = total subscribers in 2023; then 2024 total = 1.1T1.1T.

From the bar chart, in 2023: Kid = 0.15T0.15T, Elder = 0.20T0.20T.

Clue 4 gives us two fixed 2023 values:

  • Kid one-app = 10,000
  • Elder multi-app = 15,000

Clue 3 says Kid-multi (2023) = Elder-one-app (2023). Call this common value xx.

So:

  • Kid total (2023) = 10,000+x=0.15T10{,}000 + x = 0.15T
  • Elder total (2023) = x+15,000=0.20Tx + 15{,}000 = 0.20T

From the Elder equation: x=0.20T−15,000x = 0.20T - 15{,}000.

Substituting into the Kid equation: 10,000+0.20T−15,000=0.15T10{,}000 + 0.20T - 15{,}000 = 0.15T 0.05T=5,000  ⟹  T=100,0000.05T = 5{,}000 \implies T = 100{,}000

Then x=0.20×100,000−15,000=5,000x = 0.20 \times 100{,}000 - 15{,}000 = 5{,}000.

Solved 2023 Kid breakdown

Kid (2023)Count
One-app10,000
Multi-app5,000
Total15,000

Answering the question

We need the percentage of Kid subscribers who used multiple apps in 2023: 5,00015,000=13=33.33%\frac{5{,}000}{15{,}000} = \frac{1}{3} = 33.33\%

Answer: A. 33.33%

Q7Mixed Charts & CaseletsMCQ

What was the percentage increase in the number of subscribers in the 'Elder' category from 2023 to 2024?

Show solution

Correct answer: C

Finding the total and category counts

Let TT = total subscribers in 2023; then 2024 total = 1.1T1.1T.

From the bar chart:

  • 2023 Elder = 0.20T0.20T
  • 2024 Elder = 0.30×1.1T=0.33T0.30 \times 1.1T = 0.33T

We need TT. Using clues 3 and 4:

In 2023, let xx = Kid-multi = Elder-one-app (clue 3). Clue 4 gives Kid-one-app = 10,000 and Elder-multi = 15,000.

  • Kid total: 10,000+x=0.15T10{,}000 + x = 0.15T
  • Elder total: x+15,000=0.20Tx + 15{,}000 = 0.20T

From the Elder equation: x=0.20T−15,000x = 0.20T - 15{,}000.

Substitute into the Kid equation: 10,000+0.20T−15,000=0.15T10{,}000 + 0.20T - 15{,}000 = 0.15T 0.05T=5,000  ⟹  T=100,0000.05T = 5{,}000 \implies T = 100{,}000

Elder counts

YearCalculationElder count
20230.20×100,0000.20 \times 100{,}00020,000
20240.30×110,0000.30 \times 110{,}00033,000

Percentage increase

Increase=33,000−20,000=13,000\text{Increase} = 33{,}000 - 20{,}000 = 13{,}000 Percentage increase=13,00020,000×100=65%\text{Percentage increase} = \frac{13{,}000}{20{,}000} \times 100 = 65\%

Answer: C. 65%

Q8Mixed Charts & CaseletsMCQ

What could be the minimum percentage of subscribers who used multiple apps in 2024?

Show solution

Correct answer: B

Building the full 2024 picture

First, find TT (2023 total). Let xx = Kid-multi (2023) = Elder-one-app (2023) by clue 3.

  • Kid (2023): 10,000+x=0.15T10{,}000 + x = 0.15T
  • Elder (2023): x+15,000=0.20Tx + 15{,}000 = 0.20T

Solving: x=0.20T−15,000x = 0.20T - 15{,}000, so 10,000+0.20T−15,000=0.15T  ⟹  T=100,00010{,}000 + 0.20T - 15{,}000 = 0.15T \implies T = 100{,}000.

Thus 2024 total = 110,000110{,}000.

Now apply clue 2 for 2024:

  • Kid total = 0.20×110,000=22,0000.20 \times 110{,}000 = 22{,}000; one-app = 12×22,000=11,000\frac{1}{2} \times 22{,}000 = 11{,}000, so multi = 11,000.
  • Elder total = 0.30×110,000=33,0000.30 \times 110{,}000 = 33{,}000; one-app = 23×33,000=22,000\frac{2}{3} \times 33{,}000 = 22{,}000, so multi = 11,000.
  • Others total = 0.50×110,000=55,0000.50 \times 110{,}000 = 55{,}000 — but no clue tells us how Others split between one-app and multi-app.
Category (2024)One-appMulti-appTotal
Kid11,00011,00022,000
Elder22,00011,00033,000
Othersunknownunknown55,000
Total110,000

Minimising multi-app users

💡 Teacher tip: The Kid and Elder multi-app counts are fixed by clue 2. Only the Others category is flexible — so to minimise total multi-app users, push as many Others as possible into one-app (i.e., set Others-multi = 0).

Minimum multi-app total = 11,000+11,000+0=22,00011{,}000 + 11{,}000 + 0 = 22{,}000.

Minimum percentage=22,000110,000×100=20%\text{Minimum percentage} = \frac{22{,}000}{110{,}000} \times 100 = 20\%

Answer: B. 20.0%

Set · Line Graphs

The air-conditioner (AC) in a large room can be operated either in REGULAR mode or in POWER mode to reduce the temperature. If the AC operates in REGULAR mode, then it brings down the temperature inside the room (called inside temperature) at a constant rate to the set temperature in 1 hour. If it operates in POWER mode, then this is achieved in 30 minutes. If the AC is switched off, then the inside temperature rises at a constant rate so as to reach the temperature outside at the time of switching off in 1 hour. The temperature outside has been falling at a constant rate from 7 pm onward until 3 am on a particular night. The following graph shows the inside temperature between 11 pm (23:00) and 2 am (2:00) that night. The following facts are known about the AC operation that night. The AC was turned on for the first time that night at 11 pm (23:00). The AC setting was changed (including turning it on/off, and/or setting different temperatures) only at the beginning of the hour or at 30 minutes after the hour. The AC was used in POWER mode for longer duration than in REGULAR mode during this 3-hour period.

Line graph: Inside temperature (deg. C) between 11 pm (23:00) and 2 am (2:00).

TimeInside temperature (deg. C)
23:0038
23:3032
0:0026
0:3031
1:0026
1:3030
2:0028
Q9Line GraphsMCQ

How many times the AC must have been turned off between 11:01 pm and 1:59 am?

Show solution

Correct answer: B

We need to determine how many times the AC was switched off between 11:01 pm and 1:59 am.

Step 1: Read the inside-temperature graph.

TimeInside temp (°C)
23:0038
23:3032
0:0026
0:3031
1:0026
1:3030
2:0028

Step 2: Identify on/off periods.

When the AC is on (cooling), the inside temperature falls. When the AC is off, the inside temperature rises (the room warms toward the outside temperature). Checking each 30-minute segment:

SegmentInside changeAC status
23:00 → 23:3038 → 32 (falling)ON
23:30 → 0:0032 → 26 (falling)ON
0:00 → 0:3026 → 31 (rising)OFF
0:30 → 1:0031 → 26 (falling)ON
1:00 → 1:3026 → 30 (rising)OFF
1:30 → 2:0030 → 28 (falling)ON

Step 3: Count the switch-offs.

The AC was turned off at 0:00 and at 1:00 — both times fall within 11:01 pm to 1:59 am. That gives 2 switch-offs.

Answer: B. 2

Q10Line GraphsTITA

What was the temperature outside, in degree Celsius, at 1 am?

Show solution

Correct answer: 34

We need the outside temperature at 1:00 am. The key is the AC off-period that begins at 1:00.

Step 1: Identify the off-period starting at 1:00.

From the graph, the inside temperature rises from 26 °C to 30 °C between 1:00 and 1:30, which means the AC was switched off at 1:00.

TimeInside temp (°C)
1:0026
1:3030

Step 2: Apply the off-period rule.

When the AC is switched off, the inside temperature rises at a constant rate so as to reach the outside temperature at the moment of switching off in exactly 1 hour.

  • At 1:00, inside temperature = 26 °C.
  • In 30 minutes, it rose to 30 °C — a rise of 4 °C.
  • Since the rate is constant, in a full hour the rise would be 4×2=84 \times 2 = 8 °C.
  • Therefore, the outside temperature at 1:00 = 26+8=3426 + 8 = 34 °C.

Answer: 34

Q11Line GraphsTITA

What was the temperature outside, in degree Celsius, at 9 pm?

Show solution

Correct answer: 42

We need the outside temperature at 9 pm. To get there, we first determine the outside temperature at known times and then use the constant rate of change.

Step 1: Find outside temperatures using the off-periods.

When the AC is off, the inside temperature rises at a constant rate to reach the outside temperature (at the moment of switching off) in 1 hour.

Off-periodInside at switch-offRise in 30 minProjected 1-hour riseOutside temp at switch-off
0:00–0:3026 °C26 → 31 = 5 °C5×2=105 \times 2 = 10 °C26+10=3626 + 10 = 36 °C
1:00–1:3026 °C26 → 30 = 4 °C4×2=84 \times 2 = 8 °C26+8=3426 + 8 = 34 °C

So: outside(0:00) = 36 °C, outside(1:00) = 34 °C.

Step 2: Find the rate of outside temperature change.

The outside temperature falls at a constant rate from 7 pm to 3 am. Between 0:00 and 1:00 it dropped from 36 to 34:

Rate=36−341=2 °C per hour (falling)\text{Rate} = \frac{36 - 34}{1} = 2 \text{ °C per hour (falling)}

Step 3: Extrapolate back to 9 pm.

9 pm (21:00) is 3 hours before midnight (0:00). Since the outside temperature falls by 2 °C every hour, it was 2 °C higher for each hour we go back:

outside(21:00)=36+2×3=36+6=42 °C\text{outside}(21{:}00) = 36 + 2 \times 3 = 36 + 6 = 42 \text{ °C}

Answer: 42

Q12Line GraphsMCQ

What best can be concluded about the number of times the AC must have either been turned on or the AC temperature setting been altered between 11:01 pm and 1:59 am?

Show solution

Correct answer: D

We need to count how many times the AC was turned on or had its temperature setting altered between 11:01 pm and 1:59 am. Switch-offs do not count.

Step 1: Identify all on/off periods from the graph.

SegmentInside changeAC status
23:00 → 23:3038 → 32 (falling)ON
23:30 → 0:0032 → 26 (falling)ON
0:00 → 0:3026 → 31 (rising)OFF
0:30 → 1:0031 → 26 (falling)ON
1:00 → 1:3026 → 30 (rising)OFF
1:30 → 2:0030 → 28 (falling)ON

Step 2: Determine the mode for the first hour (23:00–0:00).

The inside temperature falls 38 → 32 → 26 in two 30-minute steps. There are two possibilities:

  • REGULAR mode set to 26 °C: takes 60 minutes to reach 26. At the 30-minute mark it would be at the midpoint 38+262=32\frac{38+26}{2} = 32, matching the graph. But this involves no setting change at 23:30.
  • POWER mode: set to 32 for 23:00–23:30 (reaches 32 in 30 min), then change the setting to 26 at 23:30 (reaches 26 in 30 min). This involves a setting change at 23:30.

The problem states POWER mode was used for longer than REGULAR mode. If the first hour were REGULAR (60 min of REGULAR), the remaining cooling time is only 60 minutes (0:30–1:00 and 1:30–2:00), so POWER could be at most 60 min — not strictly greater than REGULAR. This violates the constraint.

Therefore, the first hour must be POWER mode, which requires a setting change at 23:30 (from 32 to 26).

💡 Teacher tip: The constraint "POWER longer than REGULAR" is the decisive clue. It forces the first hour into POWER mode, which in turn forces a setting change at 23:30.

Step 3: List all events between 11:01 pm and 1:59 am.

Settings change only at:00 or:30. Here is the complete timeline:

TimeEventCounts?
23:30Setting altered from 32 → 26✅ Yes (setting altered)
0:00AC turned off❌ No (switch-off)
0:30AC turned on✅ Yes (turned on)
1:00AC turned off❌ No (switch-off)
1:30AC turned on✅ Yes (turned on)

Step 4: Count.

Three events qualify: the setting change at 23:30, the turn-on at 0:30, and the turn-on at 1:30.

Answer: D. Exactly 3

Q13Line GraphsTITA

What was the maximum difference between temperature outside and inside temperature, in degree Celsius, between 11:01 pm and 1:59 am?

Show solution

Correct answer: 10

We need the maximum value of (outside temperature − inside temperature) between 11:01 pm and 1:59 am.

Step 1: Establish outside temperatures at each half-hour mark.

From the off-period analysis (inside rises at a constant rate to reach the outside temperature at switch-off in 1 hour):

  • Switched off at 0:00 (inside = 26): rose 5 °C in 30 min → 10 °C in 1 hour → outside(0:00) = 26+10=3626 + 10 = 36
  • Switched off at 1:00 (inside = 26): rose 4 °C in 30 min → 8 °C in 1 hour → outside(1:00) = 26+8=3426 + 8 = 34

Outside falls at a constant rate: 36−341=2\frac{36 - 34}{1} = 2 °C/hour. Also, since the AC was first turned on at 23:00 (and was off before that), the inside had risen to match the outside, so outside(23:00) = inside(23:00) = 38.

TimeOutside (°C)Inside (°C)Outside − Inside (°C)
23:0038380
23:3037325
0:00362610
0:3035314
1:0034268
1:3033303
2:0032284

Step 2: Verify the maximum doesn't occur inside a segment.

Within each 30-minute segment, both inside and outside temperatures change linearly, so their difference also changes monotonically:

  • During cooling (AC on): inside falls faster than outside, so the difference increases throughout the segment.
  • During warming (AC off): inside rises while outside falls, so the difference decreases throughout the segment.

Since the difference is monotonic within each segment, the overall maximum must occur at one of the endpoints listed above.

Step 3: Identify the peak.

The largest difference is 10 °C at 0:00 — the moment the inside has just been cooled to 26 °C while the outside is still 36 °C. This time falls within 11:01 pm to 1:59 am.

Answer: 10

Set · Puzzles

The figure below shows a network with three parallel roads represented by horizontal lines R-A, R-B, and R-C and another three parallel roads represented by vertical lines V1, V2, and V3. The figure also shows the distance (in km) between two adjacent intersections. Six ATMs are placed at six of the nine road intersections. Each ATM has a distinct integer cash requirement (in Rs. Lakhs), and the numbers at the end of each line in the figure indicate the total cash requirements of all ATMs placed on the corresponding road. For example, the total cash requirement of the ATM(s) placed on road R-A is Rs. 22 Lakhs. The following additional information is known. 1. The ATMs with the minimum and maximum cash requirements of Rs. 7 Lakhs and Rs. 15 Lakhs are placed on the same road. 2. The road distance between the ATM with the second highest cash requirement and the ATM located at the intersection of R-C and V3 is 12 km.

Chart for this set — reading the chart is part of the question
Q14PuzzlesMCQ

Which of the following statements is correct?

Show solution

Correct answer: B

We need to determine the cash requirement at the (R-C, V2) intersection. Let's build the full arrangement from the clues.

Step 1 — Verify the grand total

Summing the horizontal road totals: 22+20+20=6222 + 20 + 20 = 62.

Summing the vertical road totals: 15+21+26=6215 + 21 + 26 = 62. ✓

So the six ATMs together hold Rs. 62 Lakhs.

Step 2 — Locate the minimum (7) and maximum (15)

Clue 1 says the ATMs with Rs. 7 Lakhs (minimum) and Rs. 15 Lakhs (maximum) are on the same road. Their sum is 7+15=227 + 15 = 22.

We check which road could hold exactly these two (or more) ATMs:

RoadTotalCould 7 and 15 be on it?
R-A22Yes — 7 + 15 = 22 exactly, so they are the only ATMs on R-A.
R-B20No — 22 > 20.
R-C20No — 22 > 20.
V115No — 22 > 15.
V221No — 22 > 21.
V326Would need a third ATM worth 26−22=426 - 22 = 4, but 4 < 7 (the minimum). No.

R-A = {7, 15}, exactly two ATMs.

Step 3 — Determine the remaining four cash values

The other four ATMs sum to 62−22=4062 - 22 = 40 and must split into R-B (20) and R-C (20).

Four distinct integers between 8 and 14 (since 7 is the min and 15 is the max) summing to 40:

  • {8, 9, 10, 13}: sum = 40, but no two pairs each total 20 (8+13 = 21, 9+10 = 19). ✗
  • {8, 9, 11, 12}: sum = 40, and 8+12 = 20, 9+11 = 20. ✓

So R-B = {8, 12}, R-C = {9, 11}, and the six values are {7, 8, 9, 11, 12, 15}.

Step 4 — Place the ATMs using Clue 2

The second-highest value is 12. Clue 2 says it is 12 km from the ATM at (R-C, V3), so there is an ATM at (R-C, V3).

Since 12 belongs to R-B, we test each possible column on R-B. Recall the road distances: V1–V2 = 4 km, V2–V3 = 7 km (along any horizontal road); R-A–R-B = 3 km, R-B–R-C = 5 km (along any vertical road).

Position of 12Path to (R-C, V3)Distance
(R-B, V1)V1→V2→V3 along R-B, then V3 down to R-C4+7+5=164 + 7 + 5 = 16 km ✗
(R-B, V2)V2→V3 along R-B, then V3 down to R-C7+5=127 + 5 = 12 km ✓
(R-B, V3)V3 down to R-C55 km ✗

So (R-B, V2) = 12.

Step 5 — Place R-C's two values

R-C = {9, 11} with an ATM at (R-C, V3). The V3 column totals 26.

  • If (R-C, V3) = 11: remaining V3 = 26−11=1526 - 11 = 15 for the R-A and R-B cells in column V3. This is achievable (see grid below).
  • If (R-C, V3) = 9: remaining V3 = 26−9=1726 - 9 = 17. R-A can contribute 7 or 15; R-B's remaining ATM is 8. The maximum fill is 15+8=2315 + 8 = 23, but we need exactly 17. If R-B contributes 8, R-A must contribute 9 — but 9 is already used by R-C. If R-B contributes nothing, R-A must contribute 17 — impossible (max is 15). ✗

So (R-C, V3) = 11 and therefore (R-C, V2) = 9.

Step 6 — Complete the grid

Column V2 = 21 = 12 (at R-B, V2) + 9 (at R-C, V2) + (R-A, V2). So (R-A, V2) = 0 → no ATM there.

R-A's 7 and 15 must occupy V1 and V3; R-B's 8 sits at V1 or V3. Two equally valid layouts remain (cells shown a / b differ between layouts; bold = fixed in both):

RoadV1V2V3Row total
R-A7 / 15—15 / 722
R-B8 / —12— / 820
R-C—91120
Col total15212662

💡 Teacher tip: Even though two layouts exist, the (R-C, V2) cell is 9 in both — the V2 column must total 21, it already holds 12 and 9, and R-A contributes nothing at V2.

Answer: Choice B — the ATM at (R-C, V2) has a cash requirement of Rs. 9 Lakhs.

Q15PuzzlesTITA

How many ATMs have cash requirements of Rs. 10 Lakhs or more?

Show solution

Correct answer: 3

We first determine the six cash values, then count how many are Rs. 10 Lakhs or more.

Step 1 — Grand total

Horizontal road totals: 22+20+20=6222 + 20 + 20 = 62.

Vertical road totals: 15+21+26=6215 + 21 + 26 = 62. ✓

Step 2 — Locate the minimum (7) and maximum (15)

Clue 1 places them on the same road; their sum is 7+15=227 + 15 = 22, which matches R-A exactly. No other road can hold both (R-B and R-C total only 20; V3 = 26 would require a third ATM worth 4, below the minimum of 7). So R-A = {7, 15}.

Step 3 — Find the remaining four values

The other four ATMs sum to 62−22=4062 - 22 = 40 and split into R-B (20) and R-C (20). Four distinct integers between 8 and 14 summing to 40:

  • {8, 9, 10, 13}: no pair of pairs each totals 20. ✗
  • {8, 9, 11, 12}: 8+12=208 + 12 = 20 and 9+11=209 + 11 = 20. ✓

So R-B = {8, 12}, R-C = {9, 11}.

Step 4 — The six cash values

Value789111215
≥ 10?NoNoNoYesYesYes

The values that are Rs. 10 Lakhs or more are 11, 12, and 15 — three ATMs.

Answer: 3

Q16PuzzlesMCQ

Which of the following two statements is/are DEFINITELY true? Statement A: Each of R-A, R-B, and R-C has two ATMs. Statement B: Each of V1, V2, and V3 has two ATMs.

Show solution

Correct answer: A

We need to check whether each statement holds in every valid layout.

Step 1 — Determine the row (horizontal road) assignments

From the clues (detailed in the full solution):

  • R-A = 22 = 7 + 15 → two ATMs
  • R-B = 20 = 8 + 12 → two ATMs
  • R-C = 20 = 9 + 11 → two ATMs

Step 2 — Determine the column (vertical road) assignments

Using Clue 2 (the second-highest value, 12, is 12 km from the ATM at (R-C, V3)), we pin (R-B, V2) = 12, (R-C, V3) = 11, and (R-C, V2) = 9. Column V2 = 21 = 12 + 9, so R-A has no ATM at V2. R-A's 7 and 15 go to V1 and V3; R-B's 8 goes to V1 or V3. This yields two valid layouts:

RoadV1V2V3Row total
R-A7 / 15—15 / 722
R-B8 / —12— / 820
R-C—91120
Col total15212662

Step 3 — Evaluate Statement A

Statement A: Each of R-A, R-B, and R-C has two ATMs.

From Step 1: R-A = {7, 15}, R-B = {8, 12}, R-C = {9, 11} — each has exactly two ATMs in both layouts. ✅

Step 4 — Evaluate Statement B

Statement B: Each of V1, V2, and V3 has two ATMs.

  • Layout 1 (R-A,V1 = 7; R-B,V1 = 8; R-A,V3 = 15; R-B,V3 empty):

  • V1: {7, 8} → 2 ATMs

  • V2: {12, 9} → 2 ATMs

  • V3: {15, 11} → 2 ATMs ✅

  • Layout 2 (R-A,V1 = 15; R-B,V1 empty; R-A,V3 = 7; R-B,V3 = 8):

  • V1: {15} → 1 ATM

  • V2: {12, 9} → 2 ATMs

  • V3: {7, 8, 11} → 3 ATMs ❌

Since Statement B fails in Layout 2, it is not definitely true.

💡 Teacher tip: "Definitely true" means true in every valid arrangement. Even one counterexample disqualifies a statement.

Answer: Choice A — Only Statement A.

Q17PuzzlesMCQ

What best can be said about the road distance (in km) between the ATMs having the second highest and the second lowest cash requirements?

Show solution

Correct answer: D

We need the road distance between the ATM with the second-highest cash requirement and the ATM with the second-lowest cash requirement.

Step 1 — Identify the six values

From the full deduction (min = 7, max = 15 on R-A; remaining four split into R-B = {8, 12} and R-C = {9, 11}):

Sorted values: 7, 8, 9, 11, 12, 15

  • Second-lowest = 8
  • Second-highest = 12

Step 2 — Locate 12

Using Clue 2, the second-highest (12) is 12 km from the ATM at (R-C, V3). Testing positions on R-B:

  • (R-B, V2) → (R-B, V3) → (R-C, V3) = 7+5=127 + 5 = 12 km ✓

So (R-B, V2) = 12 in every valid layout.

Step 3 — Locate 8

The value 8 belongs to R-B = {8, 12}. Since 12 is at V2, the 8 must be at V1 or V3. Both layouts are valid:

RoadV1V2V3Row total
R-A7 / 15—15 / 722
R-B8 / —12— / 820
R-C—91120
Col total15212662

Step 4 — Compute the distance in each layout

Both ATMs are on R-B, so the distance is purely horizontal along R-B.

  • Layout 1: 8 is at (R-B, V1), 12 is at (R-B, V2). Distance = V1→V2 = 4 km.
  • Layout 2: 8 is at (R-B, V3), 12 is at (R-B, V2). Distance = V3→V2 = 7 km.

Both layouts satisfy all clues, so the distance could be either value.

💡 Teacher tip: When two valid arrangements exist and a question asks "what best can be said," the answer must cover both possibilities.

Answer: Choice D — Either 4 km or 7 km.

Q18PuzzlesTITA

What is the number of ATMs whose locations and cash requirements can both be uniquely determined?

Show solution

Correct answer: 3

We need to count the ATMs whose location and cash requirement are both uniquely determined — meaning they are fixed in every valid layout.

Step 1 — Establish the two valid layouts

From the full deduction:

  • R-A = {7, 15}, R-B = {8, 12}, R-C = {9, 11}
  • (R-B, V2) = 12, (R-C, V2) = 9, (R-C, V3) = 11 (fixed by clues)
  • (R-A, V2) is empty (V2 = 21 = 12 + 9)
  • R-A's 7 and 15 go to V1 and V3 (in either order); R-B's 8 goes to V1 or V3
RoadV1V2V3Row total
R-A7 / 15—15 / 722
R-B8 / —12— / 820
R-C—91120
Col total15212662

Step 2 — Identify which ATMs are fixed in both layouts

ATMLayout 1Layout 2Uniquely determined?
(R-B, V2) = 12✓✓Yes
(R-C, V2) = 9✓✓Yes
(R-C, V3) = 11✓✓Yes
Value 7(R-A, V1)(R-A, V3)No — swaps position
Value 15(R-A, V3)(R-A, V1)No — swaps position
Value 8(R-B, V1)(R-B, V3)No — swaps position

💡 Teacher tip: An ATM is "uniquely determined" only if both its position and its value are the same in every valid arrangement. If either can vary, it doesn't count.

Exactly 3 ATMs — those at (R-B, V2), (R-C, V2), and (R-C, V3) — are fully determined.

Answer: 3

Set · Puzzles

The table given below shows the amount, in grams, of carbohydrate, protein, fat and all other nutrients, per 100 grams of nutrients in seven food grains. The first column shows the food grain category and the second column its codename. The table has some missing values. The following additional facts are known. 1. Both the pseudo-cereals had higher amounts of carbohydrate as well as higher amounts of protein than any millet. 2. Both the cereals had higher amounts of carbohydrate than any pseudo-cereal. 3. All the missing values of carbohydrate amounts (in grams) for all the food grains are non-zero multiples of 5. 4. All the missing values of protein, fat and other nutrients amounts (in grams) for all the food grains are non-zero multiples of 4. 5. P1 contained double the amount of protein that M3 contains.

Table: Composition per 100 grams of nutrients in seven food grains (grams). Blank cells are missing values.

Food grain CategoryCodenameCarbohydrateProteinFatOther nutrients
CerealC1012
CerealC2310
MilletM16210
MilletM2716
MilletM35612
Pseudo-cerealP16610
Pseudo-cerealP2148
Q19PuzzlesTITA

How many foodgrains had a higher amount of carbohydrate per 100 grams of nutrients than M1?

Show solution

Correct answer: 5

Setting up the full table

Every row sums to 100 g. We combine this with the divisibility rules (missing carbs are non-zero multiples of 5; missing protein/fat/other are non-zero multiples of 4) and the three ordering constraints to fill every blank.

Key deductions (worked in dependency order):

  1. M3 and P1 are linked by Clue 5.
  • M3: 56+Protein+12+Other=100⇒Protein+Other=3256 + \text{Protein} + 12 + \text{Other} = 100 \Rightarrow \text{Protein} + \text{Other} = 32, both multiples of 4.
  • P1: 66+Protein+Fat+10=100⇒Protein+Fat=2466 + \text{Protein} + \text{Fat} + 10 = 100 \Rightarrow \text{Protein} + \text{Fat} = 24, both multiples of 4.
  • Clue 5 says P1's protein =2×= 2 \times M3's protein. Testing the multiples of 4: if M3's protein were 4, P1's protein would be 8 — but P1 must beat every millet on protein (Clue 1), and M1 already has 10, so 8 is too low. The only fit is M3 protein = 8, M3 other = 24 and P1 protein = 16, P1 fat = 8.
  1. P2 (pseudo-cereal): Carb+14+Fat+8=100⇒Carb+Fat=78\text{Carb} + 14 + \text{Fat} + 8 = 100 \Rightarrow \text{Carb} + \text{Fat} = 78. Carb must be a multiple of 5, fat a multiple of 4, and P2's carb must exceed every millet's carb (M1 = 62, M3 = 56). The only pair with carb >62> 62 is carb = 70, fat = 8.

  2. Cereals must out-carb every pseudo-cereal (Clue 2): pseudo-cereals reach 66 (P1) and 70 (P2), so each cereal's carb >70> 70.

  • C1: Carb+Protein=88\text{Carb} + \text{Protein} = 88. The only multiple-of-5 / multiple-of-4 split with carb >70> 70 is 80, 8.
  • C2: Carb+Protein=87\text{Carb} + \text{Protein} = 87. The only split with carb >70> 70 is 75, 12.
  1. M2 (millet): Carb+Protein=77\text{Carb} + \text{Protein} = 77. Carb must be a multiple of 5, protein a multiple of 4, and M2 must stay below every pseudo-cereal on both carb (<66< 66) and protein (<14< 14). The only fit is carb = 65, protein = 12.

  2. M1: Fat+Other=28\text{Fat} + \text{Other} = 28 (both multiples of 4), but the individual split is not pinned down.

Solved table:

CodeCategoryCarbohydrateProteinFatOther
C1Cereal808012
C2Cereal7512310
M1Millet6210(F+O=28)(F+O=28)
M2Millet6512716
M3Millet5681224
P1Pseudo-cereal6616810
P2Pseudo-cereal701488

Answering the question

M1's carbohydrate is 62 g. We count every other grain whose carbohydrate exceeds 62:

CodeCarbohydrateHigher than 62?
C180✓
C275✓
M265✓
M356✗
P166✓
P270✓

That is 5 grains (C1, C2, M2, P1, P2).

Answer: 5

Q20PuzzlesTITA

How many grams of protein were there in 100 grams of nutrients in M2?

Show solution

Correct answer: 12

Setting up the full table

Every row sums to 100 g. Missing carbs are non-zero multiples of 5; missing protein/fat/other are non-zero multiples of 4. The ordering constraints (Clues 1–2) and the protein link (Clue 5) pin down every value except M1's fat/other split.

Key deductions:

  1. M3 & P1 (linked by Clue 5): M3: Protein + Other = 32 (both ×4). P1: Protein + Fat = 24 (both ×4), with P1-protein = 2 × M3-protein. If M3-protein = 4, then P1-protein = 8, but P1 must beat every millet on protein and M1 already has 10 — too low. So M3-protein = 8, M3-other = 24, P1-protein = 16, P1-fat = 8.

  2. P2: Carb + Fat = 78 (carb ×5, fat ×4). P2's carb must exceed every millet's (≥ 62). Only fit: carb = 70, fat = 8.

  3. Cereals must out-carb every pseudo-cereal (max pseudo-cereal carb = 70): C1: Carb + Protein = 88 → only split with carb > 70 is 80, 8. C2: Carb + Protein = 87 → only split with carb > 70 is 75, 12.

  4. M2: Carb + Protein = 77 (carb ×5, protein ×4). M2 must stay below every pseudo-cereal on carb (< 66) and protein (< 14). Only fit: carb = 65, protein = 12.

Solved table:

CodeCategoryCarbohydrateProteinFatOther
C1Cereal808012
C2Cereal7512310
M1Millet6210(F+O=28)(F+O=28)
M2Millet6512716
M3Millet5681224
P1Pseudo-cereal6616810
P2Pseudo-cereal701488

Answering the question

For M2 specifically: Carb+Protein=100−7−16=77\text{Carb} + \text{Protein} = 100 - 7 - 16 = 77. The carbohydrate must be a non-zero multiple of 5 and the protein a non-zero multiple of 4. As a millet, M2 must have less carbohydrate than every pseudo-cereal (so carb <66< 66) and less protein than every pseudo-cereal (so protein <14< 14, since P2 has 14).

The possible (carb, protein) pairs summing to 77 with the divisibility rules are (5, 72), (25, 52), (45, 32), (65, 12). Only (65, 12) satisfies protein <14< 14.

Answer: 12

Q21PuzzlesTITA

How many grams of other nutrients were there in 100 grams of nutrients in M3?

Show solution

Correct answer: 24

Setting up the full table

Every row sums to 100 g. Missing carbs are non-zero multiples of 5; missing protein/fat/other are non-zero multiples of 4. Clues 1–2 give ordering constraints; Clue 5 links P1's and M3's protein.

Key deductions:

  1. M3 & P1 (linked by Clue 5): M3: 56+Protein+12+Other=100⇒Protein+Other=3256 + \text{Protein} + 12 + \text{Other} = 100 \Rightarrow \text{Protein} + \text{Other} = 32, both multiples of 4. P1: 66+Protein+Fat+10=100⇒Protein+Fat=2466 + \text{Protein} + \text{Fat} + 10 = 100 \Rightarrow \text{Protein} + \text{Fat} = 24, both multiples of 4. Clue 5: P1-protein = 2 × M3-protein.

  2. Testing the multiples of 4 for M3's protein:

  • If M3-protein = 4 → P1-protein = 8. But Clue 1 requires P1's protein to exceed every millet's, and M1 already has protein = 10. Since 8 < 10, this fails.
  • If M3-protein = 8 → P1-protein = 16, P1-fat = 8, M3-other = 24. Check: P1-protein (16) beats every millet's protein (M1 = 10, M3 = 8, M2 will be 12) ✓.
  • Larger values of M3-protein (12, 16, …) would make P1-protein = 24+, but P1-protein + P1-fat = 24 and fat must be ≥ 4, so P1-protein ≤ 20. Hence no larger value works.

So M3-protein = 8 and M3-other = 24.

  1. Remaining grains (P2, C1, C2, M2) are filled similarly using the ordering and divisibility rules, giving:

Solved table:

CodeCategoryCarbohydrateProteinFatOther
C1Cereal808012
C2Cereal7512310
M1Millet6210(F+O=28)(F+O=28)
M2Millet6512716
M3Millet5681224
P1Pseudo-cereal6616810
P2Pseudo-cereal701488

Answering the question

For M3: Protein+Other=100−56−12=32\text{Protein} + \text{Other} = 100 - 56 - 12 = 32, both non-zero multiples of 4. With P1's protein =2×= 2 \times M3's protein and the requirement that P1's protein exceeds every millet's, the only valid split is protein = 8, other = 24.

Answer: 24

Q22PuzzlesTITA

What is the median of the number of grams of protein in 100 grams of nutrients among these food grains?

Show solution

Correct answer: 12

Setting up the full table

Every row sums to 100 g. Missing carbs are non-zero multiples of 5; missing protein/fat/other are non-zero multiples of 4. The ordering constraints (Clues 1–2) and the protein link (Clue 5) determine every protein value.

Key deductions:

  1. M3 & P1 (Clue 5): M3-protein + M3-other = 32; P1-protein + P1-fat = 24; P1-protein = 2 × M3-protein. The only multiple-of-4 solution keeping P1's protein above every millet's is M3-protein = 8, P1-protein = 16, P1-fat = 8, M3-other = 24.

  2. P2: Carb + Fat = 78; must out-carb every millet → carb = 70, fat = 8. Protein is already given as 14.

  3. Cereals must out-carb every pseudo-cereal (max = 70): C1: Carb + Protein = 88 → carb = 80, protein = 8. C2: Carb + Protein = 87 → carb = 75, protein = 12.

  4. M2: Carb + Protein = 77; must stay below pseudo-cereals on both → carb = 65, protein = 12.

  5. M1: Protein is already given as 10 (fat + other = 28, not individually fixed).

Solved table:

CodeCategoryCarbohydrateProteinFatOther
C1Cereal808012
C2Cereal7512310
M1Millet6210(F+O=28)(F+O=28)
M2Millet6512716
M3Millet5681224
P1Pseudo-cereal6616810
P2Pseudo-cereal701488

Answering the question

Collect the seven protein values:

CodeC1C2M1M2M3P1P2
Protein812101281614

Sort them in ascending order:

8, 8, 10, 12, 12, 14, 168,\ 8,\ 10,\ \mathbf{12},\ 12,\ 14,\ 16

With 7 values, the median is the 4th value, which is 12.

Answer: 12