1. P, Q and R can complete a work in 24, 6 and 12 days respectively. The work will be completed in — days if all of them are working together.

1. 2

2. 3 3⁄7

3. 4 ¼

4. 5

Answer & Explanation

Answer:- 2

Explanation :-

P’s 1 day work = 1/24, Q’s 1 day work = 1/6 R’s 1 day work = 1/12

(P+Q+R)’s 1 day work = (1/24) + (1/6) + (1/12) = 7/24

Whole work can be completed by P,Q & R together in 24/7 days or in (3 and 3/7) days

2. 10 men can complete a work in 7 days. But 10 women need 14 days to complete the same work. How many days will 5 men and 10 women need to complete the work?

1. 5

2. 6

3. 7

4. 8

Answer & Explanation

Answer:- 3

Explanation :-

10 men can complete a work in 7 days

5 man can complete the work in 7*2 = 14 days

10 women can complete a work in 14 days

1 day work of (5 men & 10 women) together = (1/14) + (1/14) =1/7

Therefore, 5 men & 10 women together can complete the work in 7 days

3. Kamal will complete work in 20 days. If Suresh is 25% more efficient than Kamal, he can complete the work in — days.

1. 14

2. 16

3. 18

4. 20

Answer & Explanation

Answer:- 2

Explanation :-

Kamal’s 1 day work = 1/20

Suresh’s 1 day work = (1/20) × (125/100) = 5/80 = 1/16

Therefore, Suresh can complete the work in 16 days

4. Anil and Suresh are working on a special assignment. Anil needs 6 hours to type 32 pages on a computer and Suresh needs 5 hours to type 40 pages. If both of them work together on two different computers, how much time is needed to type an assignment of 110 pages?

1. 7 hour 15 minutes

2. 7 hour 30 minutes

3. 8 hour 15 minutes

4. 8 hour 30 minutes

Answer & Explanation

Answer:- 3

Explanation :-

Pages typed by Anil in 1 hour = 32/6 = 16/3

Pages typed by Suresh in 1 hour = 40/5 = 8

Pages typed by Anil & Suresh together in 1 hour = 16/3 + 8 = 40/3

Time taken By Anil & Suresh together to type 110 pages = 110 × 3 /40 = 33/4

=> 8 ¼ hours

=> 8 hour 15 minutes

5. P and Q can complete a work in 20 days and 12 days respectively. P alone started the work and Q joined him after 4 days till the completion of the work. How long did the work last?

1. 5 days

2. 10 days

3. 14 days

4. 22 days

Answer & Explanation

Answer:- 2

Explanation :-

P’s 1 day work = 1/20

Work done by P in 4 days = 4 × (1/20) = 1/5

Remaining work = 1 – (1/5) = 4/5

Q,s 1 day work = 1/12

(P+Q) ‘s 1 day work = 1/20 + 1/12 = 8/60 = 2/15

P and Q together can complete the remaining work in = (4/5) / (2/15) = 6 days

Total days = 4 + 6 = 10