Twelve men take 6 hours to finish a piece of work. After the 12 men have worked for 1 hour, the contractor decides to call in 8 more men. How many more hours would 20 men take to complete the remaining work?

A) 3

B) 5

C) 2

D) 4

12 men took to 6 hours to complete the work.

It means there is 12 x 6= 72 units of work

Now 12men done work for one hour. So 12 x 1 =12 units of work completed.

Remaining work = 72-12= 60 units

Now the no of men=12+8= 20

So 60 units of work have to complete by 20 men

Therefore 60/20= 3 hours

 

Related MCQs:
  1. If 10 men can do a piece of work in 12 days, the time taken to 12 men to do the same piece of work will be?
  2. Twelve children take sixteen days to complete a work which can be completed by 8 adults in 12 days. After working for 3 days, sixteen adults left and six adults and four children joined them. How many days will it take to complete the remaining work?
  3. A is twice as good as workman as B and together they finish a piece of work in 18 days. In how many days will B alone finish the work?
  4. If 10 people can do a piece of work in 5 days, working 2 hours a day, how long will 2 people take to do the same work, working 5 hours a day?