1. A can do a piece of work in 10 days and B can do the same piece of work in 20 days. They start the work together but after 5 days. A leaves off B will do the remaining piece of work in?

A. 5 days B. 6 days C. 8 days D. 10 days

Answer: Option: A
Explanation: (A +B)’s 5 days work = 5 ([latex]\frac{1}{10}[/latex] + [latex]\frac{1}{20}[/latex] ) = ¾ Remaining work =(1 - [latex]\frac{3}{4}[/latex] ) = [latex]\frac{1}{4}[/latex] [latex]\frac{1}{20}[/latex] work is done by B in 1 day. Therefore, ¼ work is done by B in (20 x [latex]\frac{1}{4}[/latex] )i.e.., 5 days
2. A and B can together finish a work in 30 days. They worked for it for 20 days and then B left. The remaining work was done by A alone in 20 more days. Alone can finish the work in?

A. 48 days B. 50days C. 54 days D. 60 days

Answer: Option: D
Explanation: (A+ B)’s 20 day’s work =(20 x [latex]\frac{1}{30}[/latex]) = [latex]\frac{2}{3}[/latex] Remaining work = (1 - [latex]\frac{2}{3}[/latex]) = [latex]\frac{1}{3}[/latex] [latex]\frac{1}{3}[/latex] work is done by A in 20 days Whole work can be done by A in (3 x 20)days i.e.., 60 days
3. A can complete a job in 9 days. B in 10 days and C in 15 days. B and C start the work and are forced to leave after 2 days. The time taken to complete the remaining work is?

A. 6 days B. 9 days C. 10 days D. 13 days

Answer: Option: A
Explanation: (B + C)’s 2 day’s work = 2 ([latex]\frac{1}{10}[/latex] + [latex]\frac{1}{15}[/latex]) = [latex]\frac{1}{3}[/latex] Remaining work = (1 – [latex]\frac{1}{3}[/latex]) = [latex]\frac{2}{3}[/latex] [latex]\frac{1}{9}[/latex] work is done by A in 1 day Therefore [latex]\frac{2}{3}[/latex] work is done by A in (9 x [latex]\frac{2}{3}[/latex]) = 6 days
4. A, B and C together earn Rs.150 per day while A and C together earn Rs. 94 and B and C together earn Rs. 76. The daily earning of C is?

A. Rs. 75 B. Rs.56 C. Rs. 34 D. Rs.20

Answer: Option: D
Explanation: B’s daily earning = RS.(150 -94) = Rs. 56 A’s daily earning = Rs.(150 -76) = Rs.74 C’s daily earning = Rs.[150 – (56+74)] = Rs. 20
5. A can do a certain job in 12 days. B is 60% more efficient than A. Then Number of days it takes B to do the same piece of work is?

A. 6 B. 6 [latex]\frac{1}{4}[/latex] C. 7 [latex]\frac{1}{2}[/latex] D. 8

Answer: Option: C
Explanation: Ratio of times taken by A and B = 160 : 100 = 8 : 5 If A takes 8 days B takes 5 days If A takes 12 days, B takes =([latex]\frac{5}{8}[/latex] x 12) = 7 [latex]\frac{1}{2}[/latex] days

1. A can do a piece of work in 80 days. He works at it for 10 days and then B alone finishes the work in 42 days. The Two together could complete the work in?

A. 24 days B. 25 days C. 30 days D. 35 days

Answer: Option: C
Explanation: B's 1 day's work = = 5 ([latex]\frac{1}{20}[/latex] A’s 10 days work = (10 x [latex]\frac{1}{8}[/latex]) = [latex]\frac{1}{8}[/latex] Remaining work = (1 - [latex]\frac{1}{8}[/latex]) = [latex]\frac{7}{8}[/latex] Therefore 7/8 work is done by A in 42 days. Whole work will be done by A in (42 x [latex]\frac{8}{7}[/latex])i.e.., 48 days Therefore, (A+ B)’s 1 day work = ([latex]\frac{1}{80}[/latex] + [latex]\frac{1}{48}[/latex]) = [latex]\frac{8}{240}[/latex] = [latex]\frac{1}{30}[/latex]. A and B together can finish it in 30days.
2. Mahesh and Umesh can complete a work in 10 days and 15 days respectively. Umesh starts the work and after 5 days Mahesh also joins him in all the work would be completed in

A. 7 days B. 9 days C. 11 days D. None of these

Answer: Option: B
Explanation: Umesh’s 5 day’s work = 5 x [latex]\frac{1}{15}[/latex] = [latex]\frac{1}{3}[/latex] Remaining work = (1 – [latex]\frac{1}{3}[/latex]) = [latex]\frac{2}{3}[/latex] ([latex]\frac{1}{10}[/latex] + [latex]\frac{1}{15}[/latex]) work is done by both in 1 day Therefore 2/3 work is done by both in (6 x [latex]\frac{2}{3}[/latex]) = 4days. The work was completed in 9 days
3. Twelve men can complete a work in 8 days. Three days after they started the work, 3 more men joined them. In how many days will all of them together complete remaining work?

A. 2 B. 4 C. 5 D. 6

Answer: Option: B
Explanation: 1 man’s one day’s work = [latex]\frac{1}{96}[/latex] 12 men’s 3 day’s work = (3 x [latex]\frac{1}{8}[/latex]) = [latex]\frac{3}{8}[/latex] Remaining work = (1 – [latex]\frac{3}{8}[/latex]) = [latex]\frac{5}{8}[/latex] 15 men’s 1 day’s work = [latex]\frac{15}{96}[/latex] Now 15/96 work is done by them in 1day Therefore 5/8 work will be done by them in ([latex]\frac{96}{15}[/latex] x [latex]\frac{5}{8}[/latex]) i.e., 4 days
4. A is 30% more efficient than B. How much time will they, working together, take to complete a job which A alone could have done in 23 days?

A. 11 days B. 13 days C. 20 [latex]\frac{3}{7}[/latex] days D. None of these

Answer: Option: B
Explanation: Ratio of times taken by A and B = 100:130 = 10:13 Suppose B takes x days to do the work. x = [latex]\frac{(23 * 13)}{10}[/latex] = [latex]\frac{299}{10}[/latex] A's 1 day work = [latex]\frac{1}{23}[/latex]; B's 1 day work = [latex]\frac{10}{299}[/latex] (A + B)'s 1 day work = ([latex]\frac{1}{23}[/latex] + [latex]\frac{10}{299}[/latex]) = [latex]\frac{1}{13}[/latex] A and B together can complete the job in 13 days.
5. A can finish a work in 18 days B can do the same work in 15 days. B worked for 10 days and left the job. In how many days, A alone can finish the remaining work?

A. 5 B. 5 [latex]\frac{1}{15}[/latex] C. 6 D. 8

Answer: Option: C
Explanation: B's 10 day's work = [latex]\frac{1}{15}[/latex]* 10 = [latex]\frac{2}{3}[/latex] Remaining work = (1 - [latex]\frac{2}{13}[/latex]) = [latex]\frac{1}{3}[/latex] Now, 1/18 work is done by A in 1 day. 1/3 work is done by A in (18 * [latex]\frac{1}{3}[/latex]) = 6 days.

1. X and Y can do a piece of work in 20 days and 12 days respectively. X started the work alone and then after 4 days Y joined him till the completion of the work. How long did the work last?

A. 6 days B. 10 days C. 15 days D. 20 days

Answer: Option: B
Explanation: Work done by X in 4 days = ([latex]\frac{1}{20}[/latex] * 4) = [latex]\frac{1}{5}[/latex] Remaining work = (1 - [latex]\frac{1}{5}[/latex]) = [latex]\frac{4}{5}[/latex] (X + Y)'s 1 day work = ([latex]\frac{1}{20}[/latex] + [latex]\frac{1}{12}[/latex]) = [latex]\frac{2}{15}[/latex] Now, [latex]\frac{2}{15}[/latex] work is done by X and Y in 1 day. So, [latex]\frac{4}{5}[/latex] work will be done by X and Y in ([latex]\frac{15}{2}[/latex] * [latex]\frac{4}{5}[/latex]) = 6 days. Hence, total time taken = (6 + 4) = 10 days.
2. A can do a price of work in 30days while B can do it in 40 days. In how many days can A and B working together do it?

A. 70 Days B. 42 [latex]\frac{3}{4}[/latex] Days C. 27 [latex]\frac{1}{7}[/latex] Days D. 17 [latex]\frac{1}{7}[/latex] Days
Answer: Option: D
Explanation: (A +B)’s 1 day’s work = ([latex]\frac{1}{30}[/latex] + [latex]\frac{1}{40}[/latex]) = [latex]\frac{7}{120}[/latex] Time is taken by both to finish the work = [latex]\frac{120}{7}[/latex] days = 17 [latex]\frac{1}{7}[/latex] days.
3. A and B can together do a price of work in 15 days. B alone can do it in 20 days. In how many days can A alone do it?

A. 30 days B. 40 days C. 45 days D. 60days

Answer: Option: D
Explanation: A’s 1 day’s work = ([latex]\frac{1}{15}[/latex] – [latex]\frac{1}{20}[/latex]) = [latex]\frac{1}{60}[/latex] Therefore, A alone can finish = 60 days
4. Ronald and Elan are working on an assignment. Ronald takes 6 hrs to type 32 pages on a computer, while Elan takes 5 hrs to type 40 pages. How much time will they take, working together on two different computers to type an assignment of 110 pages?

A. 7 hrs 30 min B. 8 hrs C. 8 hrs 15 min D. 8 hrs 25 min

Answer: Option: C
Explanation: Number of pages typed by Ronald in 1 hour = [latex]\frac{32}{6}[/latex] = [latex]\frac{16}{3}[/latex] Number of pages typed by Elan in 1 hour = [latex]\frac{40}{5}[/latex] = 8 Number of pages typed by both in 1 hour = ([latex]\frac{16}{3}[/latex] + 8) = [latex]\frac{40}{3}[/latex] Time taken by both to type 110 pages = (110 * [latex]\frac{3}{40}[/latex]) = 8 [latex]\frac{1}{4}[/latex] = 8 hrs 15 min
5.Sakshi can do a piece of work in 20 days. Tanya is 25% more efficient than Sakshi. The number of days taken by Tanya to do the same piece of work is?

A. 15 B. 16 C. 18 D. 25

Answer: Option: B
Explanation: Ratio of times taken by Sakshi and Tanys = 125:100 = 5:4 Suppose Tanya takes x days to do the work. 5:4 :: 20:x => x= 16 days. Hence, Tanya takes 16 days to complete the work.