Question

A can do a piece of work in 12 days .B is 60% more efficient than A . what is the time taken by B to complete the same piece of work

Answer 1

According to the question ‘A’ can do a job in 12 days, that means A can do one twelfth of the total work in one day.

So, A's one days work is equal to 1/12

‘B’ is 60% more efficient than ‘A'

So, B can do 60% more work than what A do in one day.

B's one day work is equal to 1/12+60%(1/12)

i.e 1/12+1/20 taking LCM of 12 and 20, which is 60

=> 5/60+3/60 = 8/60 => 1/7.5

B's one day work is 1/7.5

So B can do the same work in 7.5 days or 7 days and 12 hours.

Answer 2

A does a work in 12 days.

In 1 day A will do 1/12 of the work.

B is 60% more efficient.

Hence B will do 1/12+60/100*1/12 of the work in 1 day.

=1/12+3/5*1/12

=1/12+1/20

=5+3/60

=8/60

=2/15

So B will complete the work in 15/2 days

=7.5 days or 7days 12 hours.

Hope its correct.