SBI PO 07 May 2017 Papers

Work done by A =

3

5

Work done by B =

2

5

∴ Time taken by A in doing 1 work =

5(x+8)

3

Time taken by B in doing 1 work =

5x

2

days
B is 20% more efficient than A.
∴

5(x+8)

3

=

5x

2

×

120

100

⇒

x+8

3

=

3x

5

⇒ 9x = 5x + 40
⇒ 4x = 40 ⇒ x = 10
∴ Time taken by A =

5×18

3

= 30 days
Time taken by B = 25 days
∴ Work done by both in 1 day =

1

30

+

1

25

=

5+6

150

=

11

150

∴ Required time =

150

11

= 13

7

11

days