Time and Work MCQs

Maths

Time and Work MCQs

Practice Time and Work MCQs with answers and detailed solutions. Learn work efficiency, pipes and cisterns, men and women work problems, partnership, wages, productivity and advanced aptitude questions commonly asked in competitive exams.

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Question #101
A is twice as efficient as B and can finish a job in 20 days less than B. In how many days can they complete the work together?
A. 12 days
B. 13(1/3) days
C. 15 days
D. 14(2/3) days

Correct Answer: Option B


Explanation:
Efficiency ratio A : B = 2 : 1. Time ratio A : B = 1 : 2. Difference = 1 part = 20 days. So A takes 20 days and B takes 40 days. Total work = 40 units. Combined efficiency = 3. Time taken together = 40 / 3 = 13(1/3) days.

This question belongs to: Maths Time and Work
Question #102
If 10 men can complete a project in 12 days, how many more men are required to finish it in 8 days?
A. 6
B. 5
C. 4
D. 8

Correct Answer: Option B


Explanation:
Using M1 * D1 = M2 * D2: 10 * 12 = M2 * 8 => 120 = 8 * M2 => M2 = 15 men. More men required = 15 - 10 = 5.

This question belongs to: Maths Time and Work
Question #103
A and B can do a piece of work in 15 days and 10 days respectively. They started the work together, but A left after 2 days. In how many days will B complete the remaining work?
A. 5 days
B. 6 days
C. 7 days
D. 6(2/3) days

Correct Answer: Option D


Explanation:
Total work = LCM(15, 10) = 30 units. Efficiency of A = 2, B = 3. Combined efficiency = 5. In 2 days, work done = 2 * 5 = 10 units. Remaining work = 30 - 10 = 20 units. Time taken by B to complete remaining work = 20 / 3 = 6(2/3) days.

This question belongs to: Maths Time and Work
Question #104
A and B can complete a piece of work in 24 days and 30 days respectively. Working together, what fraction of the work can they complete in 4 days?
A. 1/5
B. 4/15
C. 3/10
D. 7/20

Correct Answer: Option C


Explanation:
Total work = LCM(24, 30) = 120 units. Efficiency of A = 5, B = 4. Combined efficiency = 9 units/day. In 4 days, work completed = 4 * 9 = 36 units. Fraction of work completed = 36 / 120 = 3 / 10.

This question belongs to: Maths Time and Work
Question #105
A can complete a piece of work in 10 days, B in 15 days, and C in 20 days. A and C worked together for 2 days and then A was replaced by B. In how many days altogether was the work completed?
A. 9 days
B. 6 days
C. 8 days
D. 7 days

Correct Answer: Option C


Explanation:
Total work = LCM(10, 15, 20) = 60 units. Efficiency of A = 6, B = 4, C = 3. A and C work for 2 days: work done = 2 * (6 + 3) = 18 units. Remaining work = 60 - 18 = 42 units. B and C complete remaining work together with efficiency = 4 + 3 = 7 units/day. Time taken for remaining work = 42 / 7 = 6 days. Total time = 2 + 6 = 8 days.

This question belongs to: Maths Time and Work
Question #106
If 8 men and 12 boys can finish a piece of work in 10 days, while 6 men and 8 boys can finish it in 14 days, find the time taken by 1 man alone to complete the work.
A. 120 days
B. 140 days
C. 160 days
D. 100 days

Correct Answer: Option B


Explanation:
Total work = 10 * (8M + 12B) = 14 * (6M + 8B) => 80M + 120B = 84M + 112B => 4M = 8B => 1M = 2B. Total work = 10 * (8M + 6M) = 140M. Thus, 1 man alone will take 140 days.

This question belongs to: Maths Time and Work
Question #107
A, B and C can complete a piece of work in 10, 12 and 15 days respectively. They started the work together, but A left after 2 days and B left 3 days before the completion of the work. Find the total duration of the work.
A. 9 days
B. 6 days
C. 8 days
D. 7 days

Correct Answer: Option D


Explanation:
Total work = LCM(10, 12, 15) = 60 units. Efficiency of A = 6, B = 5, C = 4. Let the work last for x days. A works for 2 days: work = 12 units. B works for (x - 3) days: work = 5(x - 3). C works for x days: work = 4x. Total work = 12 + 5x - 15 + 4x = 60 => 9x - 3 = 60 => 9x = 63 => x = 7 days.

This question belongs to: Maths Time and Work
Question #108
A can finish a work in 12 days and B can do it in 15 days. After A had worked for 3 days, B also joined him to finish the remaining work. In how many days was the remaining work completed?
A. 3 days
B. 6 days
C. 4 days
D. 5 days

Correct Answer: Option D


Explanation:
Total work = LCM(12, 15) = 60 units. Efficiency of A = 5, B = 4. In 3 days, A completed 3 * 5 = 15 units. Remaining work = 60 - 15 = 45 units. Combined efficiency of A and B = 5 + 4 = 9 units/day. Time taken for remaining work = 45 / 9 = 5 days.

This question belongs to: Maths Time and Work
Question #109
A and B can complete a piece of work in 20 days and 30 days respectively. They work together for some days and then A leaves. If B completes the remaining work in 10 days, for how many days did they work together?
A. 6 days
B. 10 days
C. 8 days
D. 12 days

Correct Answer: Option C


Explanation:
Total work = LCM(20, 30) = 60 units. Efficiency of A = 3, B = 2. B works alone for 10 days: work completed = 10 * 2 = 20 units. Remaining work = 60 - 20 = 40 units. This was done by A and B together. Combined efficiency = 3 + 2 = 5 units/day. Days worked together = 40 / 5 = 8 days.

This question belongs to: Maths Time and Work
Question #110
A, B and C can complete a piece of work in 10, 15 and 20 days respectively. They started together but A left after 2 days and B left 2 days before the completion of the work. Find the total number of days taken to complete the work.
A. 7 days
B. 9 days
C. 6 days
D. 8 days

Correct Answer: Option D


Explanation:
Total work = LCM(10, 15, 20) = 60 units. Efficiency of A = 6, B = 4, C = 3. Let the total work last for x days. A worked for 2 days, so work done = 2 * 6 = 12 units. Remaining work = 60 - 12 = 48 units. B worked for (x - 2) days and C worked for x days. Therefore, 4(x - 2) + 3x = 48 => 4x - 8 + 3x = 48 => 7x = 56 => x = 8 days.

This question belongs to: Maths Time and Work
Question #111
If 12 men or 18 women can reap a field in 14 days, then the number of days that 8 men and 16 women will take to reap it is:
A. 10 days
B. 7 days
C. 9 days
D. 8 days

Correct Answer: Option C


Explanation:
12 Men = 18 Women => 1 Man = 1.5 Women. 8 men + 16 women = 8 * 1.5 + 16 = 12 + 16 = 28 women. Since 18 women take 14 days, 28 women will take (18 * 14) / 28 = 252 / 28 = 9 days.

This question belongs to: Maths Time and Work
Question #112
A can do a piece of work in 24 days and B in 30 days. They work together for 6 days and then A leaves. How many days will B take to complete the remaining work?
A. 15 days
B. 18.5 days
C. 16.5 days
D. 14 days

Correct Answer: Option C


Explanation:
Total work = LCM(24, 30) = 120 units. Efficiency of A = 5, B = 4. Combined efficiency = 9. In 6 days, work done = 6 * 9 = 54 units. Remaining work = 120 - 54 = 66 units. Time taken by B to complete the remaining work = 66 / 4 = 16.5 days.

This question belongs to: Maths Time and Work
Question #113
A can complete a project in 20 days and B in 30 days. If they work on alternate days starting with A, in how many days will the project be completed?
A. 26 days
B. 25 days
C. 24 days
D. 22 days

Correct Answer: Option C


Explanation:
Total work = LCM(20, 30) = 60 units. Efficiency of A = 3, B = 2. In a 2-day cycle (A then B), work completed = 3 + 2 = 5 units. Number of cycles required = 60 / 5 = 12 cycles. Total time = 12 * 2 = 24 days.

This question belongs to: Maths Time and Work
Question #114
A is twice as fast as B and B is twice as fast as C. If they together can complete a work in 4 days, in how many days can C alone complete it?
A. 16 days
B. 24 days
C. 32 days
D. 28 days

Correct Answer: Option D


Explanation:
Let efficiency of C = 1, then B = 2 and A = 4. Combined efficiency = 1 + 2 + 4 = 7 units/day. Total work = 4 * 7 = 28 units. Time taken by C alone = 28 / 1 = 28 days.

This question belongs to: Maths Time and Work
Question #115
A and B can do a piece of work in 10 days, B and C in 12 days, and C and A in 15 days. How long will C alone take to complete the work?
A. 60 days
B. 40 days
C. 24 days
D. 30 days

Correct Answer: Option B


Explanation:
Total work = LCM(10, 12, 15) = 60 units. Efficiency of (A+B) = 6, (B+C) = 5, (C+A) = 4. Summing gives 2*(A+B+C) = 15 => Efficiency of (A+B+C) = 7.5. Efficiency of C = (A+B+C) - (A+B) = 7.5 - 6 = 1.5. Time taken by C alone = 60 / 1.5 = 40 days.

This question belongs to: Maths Time and Work
Question #116
A can finish a work in 15 days and B in 20 days. They work together for 6 days and then B leaves. In how many days will A finish the remaining work?
A. 5 days
B. 4.5 days
C. 6 days
D. 3.5 days

Correct Answer: Option B


Explanation:
Total work = LCM(15, 20) = 60 units. Efficiency of A = 4, B = 3. Combined efficiency = 7. In 6 days, work done = 6 * 7 = 42 units. Remaining work = 60 - 42 = 18 units. Time taken by A to complete remaining work = 18 / 4 = 4.5 days.

This question belongs to: Maths Time and Work
Question #117
A and B together can do a piece of work in 9 days. If A does thrice the work of B in a given time, how many days will A alone take to complete the total work?
A. 12 days
B. 18 days
C. 15 days
D. 16 days

Correct Answer: Option A


Explanation:
Ratio of efficiency of A : B = 3 : 1. Combined efficiency = 3 + 1 = 4. Total work = 9 * 4 = 36 units. Time taken by A alone = 36 / 3 = 12 days.

This question belongs to: Maths Time and Work
Question #118
A can complete a piece of work in 16 days and B in 12 days. Starting with A, they work on alternate days. In how many days will the total work be completed?
A. 12(2/3) days
B. 13(3/4) days
C. 14 days
D. 13(1/2) days

Correct Answer: Option B


Explanation:
Total work = LCM(16, 12) = 48 units. Efficiency of A = 3, B = 4. In a 2-day cycle (A then B), work completed = 3 + 4 = 7 units. In 6 cycles (12 days), work completed = 7 * 6 = 42 units. Remaining work = 48 - 42 = 6 units. On Day 13, A works and completes 3 units. Remaining work = 3 units. On Day 14, B works with efficiency 4, so time taken = 3/4 day. Total time = 12 + 1 + 3/4 = 13(3/4) days.

This question belongs to: Maths Time and Work
Question #119
4 men and 6 women can complete a work in 8 days, while 3 men and 7 women can complete it in 10 days. In how many days will 10 women complete the work?
A. 50 days
B. 40 days
C. 45 days
D. 35 days

Correct Answer: Option B


Explanation:
Total work = 8 * (4M + 6W) = 10 * (3M + 7W) => 32M + 48W = 30M + 70W => 2M = 22W => 1M = 11W. Total work = 8 * (4*11W + 6W) = 8 * 50W = 400W. Time taken by 10 women = 400W / 10W = 40 days.

This question belongs to: Maths Time and Work
Question #120
A and B can do a work in 12 days, B and C in 15 days, and C and A in 20 days. How many days will A alone take to finish the work?
A. 30 days
B. 40 days
C. 20 days
D. 60 days

Correct Answer: Option A


Explanation:
Total work = LCM(12, 15, 20) = 60 units. Efficiency of (A+B) = 5, (B+C) = 4, (C+A) = 3. Summing efficiencies gives 2*(A+B+C) = 12 => Efficiency of (A+B+C) = 6 units/day. Efficiency of A = (A+B+C) - (B+C) = 6 - 4 = 2 units/day. Time taken by A alone = 60 / 2 = 30 days.

This question belongs to: Maths Time and Work