**Home > Quantitative Aptitude > Time and Work > Time and Work**

1. A and B together can do a piece of work in 30 days. A having worked for 16 days, B finishes the remaining work alone in 44 days. In how many days shall B finish the whole work alone?

AnswerAnswer: OptionA Explanation:

Let A's 1 day's work = x and B's 1 day's work =y. Then, x+y = 1/30 and 16x + 44y =1. Solving these two equations, we get : x = 1/60 and y = 1/60. therefore B's 1 day's work = 1/60. Hence, B alone shall finish the whole work in 60 days.

Report

Mail id:

2. A does 4/5 of a work in 20 days. He than calls in B and they together finish the remaining work in 3 days. How long B alone would take to do the whole work?

AnswerAnswer: OptionD Explanation:

Whole work is done by A in (20*5/4) = 25 days. Now, (1- 4/5) i.e., 1/5 work is done by A and B in 3 days. Whole work will be done by A and B in (3*5) = 15 days. A's 1 day's work = 1/25, (A+B)'s 1 day's work = 1/15. therefore B's 1 day's work = (1/15 - 1/25) = 4/150 = 2/75. So, B alone would do the work in 75/2 = 37 1/2 days.

Report

Mail id:

3. A, B and C together can complete a piece of work in 10 days. All the three started working at it together and after 4 days A left. Then B and C together complete the work in 10 more days. A alone could complete the work in?

AnswerAnswer: OptionC Explanation:

Work done by A, B and C in 4 days = (1/10*4) = 2/5. Remaining work =(1- 2/5) =3/5. Now, 3/5 work is done by B and C in 10 days. whole work will be done by B and C in (10*5/3) = 50/3 days. (A+B+C)'s 1 day's work = 1/10, (B+C)'s 1 day's work = 3/50. A's 1 day's work =(1/10 - 3/50) = 2/50 =1/25. therefore A alone could complete the work in 25 days.

Report

Mail id:

4. X can do a piece of work in 40 days. He works at it for 8 days and then Y finished it in 16 days. How long will they together take to complete the work?

AnswerAnswer: OptionA Explanation:

Work done by X in 8 days = (1/40*8) = 1/5. Remaining work = (1- 1/5) = 4/5. Now, 4/5 work is done by Y in 16 days. whole work will be done by Y in (16*5/4) = 20 days. therefore X's 1 day's work = 1/40, Y's 1 day's work = 1/20. (X+Y)'s 1 day's work = (1/40+ 1/20) = 3/40. Hence, X and Y will together complete the work in 40/3 = 13 1/3 days.

Report

Mail id:

5. A and B can together finish a work in 30 days. They worked together for 20 days and then B left. After another 20 days, A finished the remaining work. In how many days A alone can finish the job?