IBPS RRB Office Assistant 2018 Paper

Let, the time taken by A and B be 5x and 3x respectively.
According to the question,
Time taken by A to do the work =5x
⇒ 40 = 5x
∴ x=8
Now, time taken by B to do the work
= 3 x 8 = 24 h
∵ (A+B) 's 1 day work =

1

40

+

1

24

=

3+5

120

=

8

120

=

1

15

∴ Time taken to complete the work by both
=

1

1 15

=15 days