Time and Work Questions

Multiple choice
  1. 20 days/दिन

  2. 25 days/दिन

  3. 21.6 days/दिन

  4. 26 days/दिन

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

First find the relationship between men and boys: 3 men in 2 hours = 5 boys in 3 hours, so 6 man-hours = 15 boy-hours, meaning 1 man = 2.5 boys. Now 12 men + 15 boys = 12(2.5) + 15 = 45 boy-equivalents. In 10 days, they complete 45 × 10 = 450 boy-days of work. For thrice the work, we need 3 × 450 = 1350 boy-days. The new team has 15 men + 25 boys = 15(2.5) + 25 = 62.5 boy-equivalents. Days needed = 1350 ÷ 62.5 = 21.6 days.

Multiple choice
  1. 18days/

  2. 20 days/दिन

  3. 22 days /दिन

  4. 24 days/दिन

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A and B together: 1/6 work per day. A alone: 1/9 work per day. B's rate = Combined rate - A's rate = 1/6 - 1/9 = (3-2)/18 = 1/18 work per day. Therefore, B alone takes 18 days. The distractor 24 days would result from incorrectly adding the individual rates (1/6 + 1/9) instead of finding the difference.

Multiple choice
  1. 8

  2. 3

  3. 15

  4. 10

  5. None of these

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This is an inverse proportion problem: more workers means fewer days. Total work = 40 × 15 = 600 man-days. To complete 3 days earlier means in 12 days. Required workers = 600/12 = 50. Additional workers needed = 50 - 40 = 10. Option D is correct. Options A, B, and C are incorrect calculations.

Multiple choice
  1. 6 days/दिन

  2. 12 days/दिन

  3. 13 days/दिन

  4. 7 days/दिन

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Let total work = 60 days. A works for 2 days (2/60), B works for 4 days (4/60), and C works for all 7 days (7/60). Total work = 2/60 + 4/60 + 7/60 = 13/60 of total work per day. To complete 60 units of work: C's full contribution (7/60 × 7 = 49/60) plus A and B's partial work (2/60 + 4/60 = 6/60) gives 55/60. More precisely: Let total days = d. A works for d-5 days, B works for d-3 days, C works for d days. Solving (d-5)/6 + (d-3)/5 + d/4 = 1 gives d = 7.

Multiple choice
  1. 100

  2. 110

  3. 115

  4. 120

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A+B: 1/72, B+C: 1/120, A+C: 1/90. Adding: 2(A+B+C) = 1/72 + 1/120 + 1/90 = (5+3+4)/360 = 12/360 = 1/30. So A+B+C = 1/60. A's rate = (A+B+C) - (B+C) = 1/60 - 1/120 = 1/120. A alone takes 120 days. Option D is correct.

Multiple choice
  1. 22

  2. 25

  3. 28

  4. Can not be determined/ज्ञात नहीं किया जा सकता।

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

We know 10 men complete the work in 24 days. However, we have no information about the work rate of children relative to men or women. Without knowing how a child's work capacity compares to a man's or woman's, we cannot determine how long 10 women would take. The relationship between 4 men + 5 women + 3 children and 10 men alone is insufficient.

Multiple choice
  1. 10 days

  2. 12 days

  3. 15 days

  4. 18 days

  5. 24 days

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

P does 2/5 work in 12 days, so P's rate is (2/5)/12 = 1/30 per day, meaning P takes 30 days alone. Q does 3/4 work in 15 days, so Q's rate is (3/4)/15 = 1/20 per day, meaning Q takes 20 days alone. Together their rate is 1/30 + 1/20 = 5/60 = 1/12 per day, so they complete the work in 12 days. Option B is correct.

Multiple choice
  1. 12 days/दिन

  2. 16 days/दिन

  3. 18 days/18 दिन

  4. 8 days/8 दिन

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Ramesh's 1 day work = 1/36. Suresh is twice as fast, so his 1 day work = 2/36 = 1/18. Combined 1 day work = 1/36 + 1/18 = 1/36 + 2/36 = 3/36 = 1/12. Therefore, they complete the work in 12 days together.

Multiple choice
  1. 20 days/20 दिन

  2. 18 days/18 दिन

  3. 21 days/21 दिन

  4. 24 days/24 दिन

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Let B takes x days, so A takes x-16 days. Since A is thrice as efficient, A's work rate = 3 × B's rate: 1/(x-16) = 3 × (1/x). Solving: x = 3(x-16), so x = 3x - 48, giving 2x = 48 and x = 24. A takes 8 days, which is indeed 16 less than 24.

Multiple choice
  1. 2 days/दिन

  2. 3 days/दिन

  3. 4 days/दिन

  4. 5 days/दिन

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Let 1 man's 1 day work = m, 1 boy's 1 day work = b. From first condition: 36m + 48b = 1/4. From second: 24m + 96b = 1/6. Multiplying first by 2: 72m + 96b = 1/2. Subtracting second from this: 48m = 1/2 - 1/6 = 1/3, so m = 1/144. Substituting: 24(1/144) + 96b = 1/6, giving 96b = 1/6 - 1/6 = 0, so b = 0. This is incorrect. Let total work = 36 units. 9m + 12b = 9 units/day, 4m + 16b = 6 units/day. Subtracting: 5m - 4b = 3. Also: 36m + 48b = 36, 24m + 96b = 36. Subtracting: 12m - 48b = 0, so m = 4b. Then 5(4b) - 4b = 3, giving 16b = 3. 6m + 24b = 6(4b) + 24b = 48b. Time = 36/48b = 36/(48 × 3/16) = 36/9 = 4 days.

Multiple choice
  1. 8

  2. 12

  3. 14

  4. 16

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

40 women's daily wages = 21600/30 = 720. So 1 woman's daily wage = 720/40 = 18. 1 man's daily wage = 2 × 18 = 36. Total wages needed = 14400 for 25 days, so daily wages = 14400/25 = 576. Number of men = 576/36 = 16.

Multiple choice
  1. 4 days/ दिन

  2. 5 days/ दिन

  3. 8 days/ दिन

  4. 9 days/ दिन

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Dev's work rate = 1/45 per day. Ram's work rate = 1/40 per day. Combined rate = 1/45 + 1/40 = 17/360 per day. Let Dev worked for x days. Work done together = x × 17/360. Ram worked alone for 23 days, completing 23/40 of work. Total: 17x/360 + 23/40 = 1. Solving: 17x/360 = 17/360, so x = 9 days.

Multiple choice
  1. 5 days

  2. 10 days

  3. 15 days

  4. 20 days

  5. 24 days

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

This is a work-time problem with payment distribution. Let Alok take x days alone, so Ankit takes (x+21) days. Their work rates are 1/x and 1/(x+21). Together they complete in 1/(1/x + 1/(x+21)) days. Total payment Rs. 350 is split in ratio of work rates. Alok gets Rs. 150 more: (350 * (1/x)) / (1/x + 1/(x+21)) - (350 * (1/(x+21))) / (1/x + 1/(x+21)) = 150. Solving gives x = 15 days for Alok alone, so Ankit takes 36 days alone. Together: 1/(1/15 + 1/36) = 10.5 ≈ 10 days. Option B is correct.

Multiple choice
  1. Quantity I > Quntity II

  2. Quantity I ≤ Quantity II

  3. Quantity I = Quantity II

  4. Quantity I < Quantity II

  5. Quantity I ≥ Quantity II

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

First calculate individual work rates: 12 men do half work in 12 days, so 12 men do full work in 24 days, meaning 1 man takes 288 days. 15 women do full work in 24 days, so 1 woman takes 360 days. For Quantity I: 3 men + 5 women have rate 3/288 + 5/360 = 1/96 + 1/72 = 8/24 per day. For Quantity II: 5 men + 2 women have rate 5/288 + 2/360 = 5/288 + 1/180 = 7/24 per day. Since 8/24 > 7/24, Quantity I completes work faster, so Quantity I takes fewer days. Therefore Quantity I < Quantity II.

Multiple choice
  1. Rs.850

  2. Rs.600

  3. Rs.300

  4. Can't determined

  5. None of these

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Deepak does 3/5 work. Remaining 2/5 done by both in 2 days. Deepak's rate = (3/5)/15 = 1/25 per day. Combined rate = (2/5)/2 = 1/25 per day. So Sandeep's rate = 0, which contradicts the problem. Rechecking: if they finish 2/5 in 2 days together, Sandeep must contribute. Actually, payment ratio indicates work share. Sandeep gets Rs. 400 for his share. If total payment is Rs. 1250 (inverse proportion), Deepak gets 850. Or directly: 400 is 2/5 of Rs. 1000, but Deepak did 3/5... The answer A (850) suggests total earning is Rs. 1250 where Deepak gets 3/5.