Time and Work Questions

Multiple choice
  1. Rs. 900

  2. Rs. 450

  3. Rs. 1200

  4. Rs. 500

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

Let x be the wage for site 1 and y for site 2. 2x + 5y = 5400 and 4x + 9y = 9900. Multiplying the first by 2 gives 4x + 10y = 10800. Subtracting the second equation gives y = 900. Substituting back, 2x + 4500 = 5400, so 2x = 900, x = 450.

Multiple choice
  1. Rs. 4500

  2. Rs. 6000

  3. Rs. 7500

  4. Rs. 3600

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

Let x be the wage per day at site 1 and y be the wage per day at site 2. 2x + 5y = 5400 and 4x + 9y = 9900. Multiplying the first by 2 gives 4x + 10y = 10800. Subtracting the second from this gives y = 900. Then 2x + 5(900) = 5400, so 2x = 900, x = 450. Akash's wages: 4(450) + 3(900) = 1800 + 2700 = 4500.

Multiple choice
  1. 8

  2. 7

  3. 6

  4. 5

  5. 4

Reveal answer Fill a bubble to check yourself
D Correct answer
Multiple choice
  1. 5 days

  2. 7 days

  3. 8 days

  4. 9 days

  5. 11 days

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

Let x be the days they worked together. (x/70 + x/60) + 47/60 = 1. (x/70 + x/60) = 13/60. x * (6+7)/420 = 13/60. x * 13/420 = 13/60. x = 420/60 = 7.

Multiple choice
  1. 40

  2. 30

  3. 20

  4. 15

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

Work done in 5 days by 20 men = 1/4. Remaining work = 3/4. Men required for 3/4 work in 5 days: (20 men * 5 days) / (1/4 work) = (M * 5 days) / (3/4 work). 20 * 5 * 4 = M * 5 * (4/3) -> M = 60. Additional men needed = 60 - 20 = 40.

Multiple choice
  1. 11th day

  2. 13th day

  3. 15th day

  4. 18th day

  5. None of these

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

X is 60% more efficient than Y, so X/Y = 160/100 = 8/5. If X takes 23 days, the total work is 8 * 23 = 184 units. Y's efficiency is 5 units/day. Together, they do 13 units/day. 184/13 is approximately 14.15, meaning they finish on the 15th day.

Multiple choice
  1. 26

  2. 20

  3. 12

  4. 15

  5. 14

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

Using the formula (M1 * D1 * H1) = (M2 * D2 * H2), we have (10 * 60 * 9) = (M2 * 30 * 5). Solving for M2 gives 5400 / 150 = 36 men. Since 10 men were already working, the additional men required is 36 - 10 = 26.

Multiple choice
  1. 4 days

  2. 5 days

  3. 7 days

  4. 10 days

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

If A is 25% as efficient as B, then B is 4 times as efficient as A. If A takes x days, B takes x/4 days. Given x = (x/4) + 15, we find 3x/4 = 15, so x = 20. A takes 20 days and B takes 5 days. Together, they take (20 * 5) / (20 + 5) = 100 / 25 = 4 days.

Multiple choice
  1. 7/80

  2. 5/80

  3. 1/20

  4. 3/40

  5. 5

Reveal answer Fill a bubble to check yourself
A Correct answer
Multiple choice
  1. 16

  2. 24

  3. 18

  4. 20

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

Let A and B take x and y days to complete the work. (1/3)x + (2/3)y = 40 and (2/3)x + (1/3)y = 35. Multiply by 3: x + 2y = 120 and 2x + y = 105. Solving gives x=30, y=45. Together: 1/(1/30 + 1/45) = 1/(3/90 + 2/90) = 90/5 = 18 days.