Question

Neena can finish a project in 30days bina and cia can do same work 15 and 20 days respectively.veena and cia start working but quit after 5 days

Answer 1

We analyze the question as follows :

Neena = 30 days

Bina = 15 days.

Cia = 20 days

In one day the amount of work done by the three is :

1/30 + 1/20 + 1/15 = 3/20

If Neena and Cia leaves in 5 days we need to get the amount of work remaining.

In 5 days the work done is :

3/20 × 5 = 3/4

Work remaining = 1 - 3/4 = 1/4

We need to calculate number of days taken by Bina to finish the remaining piece of work.

In 1 day Bina does :

= 1/15 of the work

How many days will it take to finish 1/4

1/4 × 15/1 × 1 = 15/4 = 3.75

= 3.75 days