# Quantitative Aptitude: Time and Work Set 27

1. A, B and C alone can do a work in 8 days , 12 days and 6 days respectively. Find how many days they take together to complete work ?
6 days
8 days
2 2/3 days
4 days
3 days
Option C
LCM of 8 , 12 and 6 = 24
total work = 24
efficiency of A = 24/8 = 3
efficiency of B = 24/12 = 2
efficiency of C = 24/6 = 4
time taken = 24/9 = 2 2/3 days

2. P and Q alone can do a work in 30 days and 20 days respectively. P works for 15 days and left the work, remaining work done by B. Find how many days required to complete the remaining work ?
10 days
8 days
20 days
18 days
16 days
Option A
LCM of 30 and 20 = 60
total work = 60
efficiency of P = 60/30 = 2
efficiency of Q = 60/20 = 3
P completed work in 15 days = 15 * 2 = 30
time taken by Q to complete remaining work = 60 – 30 /3 = 10 days

3. A can complete 40% of work in 8 hours and while B alone can do the same work in 24 hours. Find the time taken by A and B together to complete the 60% of the work ?
5 2/3 days
8 3/5 days
4 days
6 6/11 days
8 days
Option D
A alone can do all work = 8/40 * 100 = 20 days
LCM of 20 and 24 = 120
efficiency of A = 120/20 = 6
efficiency of B = 120/24 = 5
time taken by A and B together to complete 60% of the work = 120/11 * 60/100 = 6 6/11 days

4. A and B alone can do a piece of work in 12 hours and 15 hours respectively. If they do the work alternatively for 1 hours each starting with A, then find how many hours will the work be completed ?
5 hours
3 hours
8 1/5 hours
12 1/4 hours
13 1/4 hours
Option E
LCM of 12 and 15 = 60
total work = 60
efficiency of A = 60/12 = 5
efficiency of B = 60/15 = 4
work completed in 2 hours = 5 + 4 = 9 works
(2 * 6) hours = (9 * 6) work
12 hours = 54 works
A works in another hours = 5 work
remaining 1 work completed by B = 14 hours
total time = 12 + 1 + 1/4 = 13 1/4 hours

5. A, B and C alone can do a piece of work in 3 days. If A alone can do in 6 days and C alone can do it in 18 days, how long will B alone take to complete the work ?
8 days
9 days
18 days
6 days
4 days
Option B
LCM of 3, 6 and 18 = 18
total work = 18
efficiency of A, B and C = 18/3 = 6
efficiency of A = 18/6 = 3
efficiency of C = 18/18 = 1
efficiency of B = 6 – ( 3 + 1 ) = 2
B alone can do the work = 18/2 = 9 days

6. P and Q undertook to do a piece of work for rs.3500. P alone can do it in 12 days and Q alone in 20 days. If they finished the work with the help of R in 6 days. What is share of R ?
800
700
850
650
725
Option B
LCM of 12, 20 and 6 = 60
efficiency of P = 60/12 = 5
efficiency of Q = 60/20 = 3
efficiency of P, Q and R = 60/6 = 10
efficiency of R = 10 – ( 5 + 3 ) = 2
share of R = 3500 * 2 / 10 = 700

7. Rita and Gita can do a piece of work individually in 40 days and 60 days respectively. If they work on alternate days starting with Gita, then in how many days will the work get finished ?
28 days
24 days
17 days
48 days
46 days
Option D
LCM of 40 and 60 = 120
efficiency of Rita = 120/40 = 3
efficiency of Gita = 120/60 = 2
starting with Gita work completed in 2 days = 5
time required to complete total work = 24 * 2 = 48 days

8. A and B can do a work in 12 days. B and C can do the same work in 20 days. A and C can also do the same work in 30 days. If they all work together in how many days will they complete the work ?
10 days
14 days
12 days
13 days
15 days
Option C
LCM of 12, 20 and 30 = 120
efficiency of A and B = 120/12 = 10
efficiency of B and C = 120/20 = 6
efficiency of A and C = 120/30 = 4
A + B + B + C + A + C = 10 + 6 + 4 = 20
2(A + B + C) = 20
A + B + C = 10
time 120/10 = 12 days

9. 8 men or 12 women can finish a work in 25 days. How many days will 6 men ad 11 women can finish the same work ?
15 days
14 days
28 days
30 days
32 days
Option A
8 men = 12 women
men/women = 12/8 = 3/2
total work = 8 * 3 * 25 = 600
time required = 600 /(6 * 3 + 11 * 2) = 600/40 = 15 days

10. A, B and C can complete a job in 9 days, 10 days and 15 days respectively. A, B and C start the work together and after 2 days B and C leave the work. Find how many days taken by A to complete the remaining work ?
6 days
18 days
14 days
4 days
8 days
Option D
LCM of 9, 10 and 15 = 90
efficiency of A = 90/9 = 10
efficiency of B = 90/10 = 9
efficiency of C = 90/15 = 6
A, B and C complete work in 2 days = 2(10 + 9 + 6) = 50
remaining work = 90 – 50 = 40
time taken by A to complete remaining work = 40/10 = 4 days