Important Questions on Time and Work for IBPS Bank PO Exam

Important Facts and Formulae

If A can do a piece of work in n days then A's 1 day's work =1/n If A's 1 day's work=1/n, then A can finish the work in n days. If A is thrice as good as workman as B,then: Ratio of work done by A and B = 3:1 Ratio of times taken by A and B to finish a Work =1:3

(1)P can complete a work in 12 days working 8 hours a day.Q can complete the same work in 8 days working 10 hours a day.If both P and Q work together,working 8 hours a day,in How many days can they complete the work?(Asked in Bank PO Exam 1999)

• 60/11
• 61/11
• 71/11
• 72/11

(2)A and B can do a work in 12 days,B and C can do the same work in 12 days.A,B and C together can finish it in 6 days.A and C together will do it in:

• 5 days
• 47/6 days
• 10 days
• 47/3 days

(3)A and B can do a work in 8 days,B and C can do the same work in 12 days.A,B and C together can finish it in 6 days.A and C together will do it in:

• 4 days
• 6 days
• 8 days
• 12 days

(4)A and B can do a piece of work in 72 days,B and C can do it in 120 days,A and C can do it in 90 days.In what time can A alone do it?

• 80 days
• 100 days
• 120 days
• 150 days

(5)A works twice as fast as B.If B can complete a work in 12 days independently,the number of days in which A and B can together finish the work is:

• 4 days
• 6 days
• 8 days
• 18 days

(6)A is thrice as good a workman as B and therefore is able to finish a job in 60 days less than B.Working together,they can do it in:

• 20 days
• 45/2 days
• 25 days
• 30 days

(7)A and B can do a job together in 7 days.A is 7/4 times as efficient as B.The same job can be done by A alone in:

• 28/3
• 11 days
• 49/4
• 49/3

(8)A can do  a work in 15 days and B in 20 days.If they work on it together for 4 days,then the fraction of the work that is left is:

• 1/4
• 1/10
• 7/15
• 8/15

(9)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?(bank Po 2004)

• 6 days
• 10 days
• 15 days
• 20 days

(10)A and B can do a piece of work in 30 days,while B and C can do the same work in 24 days and C and A in 20 days.They all work together for 10 days when B and C leave.How many days more will A take to finish the work?

• 18 days
• 24 days
• 30 days
• 36 days

Answers

Question Number	Answer
1	60/11
2	10 days
3	8 days
4	120 days
5	4 days
6	45/2 days
7	11 days
8	8/15
9	10 days
10	18 days