Question

Anita, indu and geeta can do a piece of work in 18 days, 27 days and 36 days respectively. They start working together. After working for 4 days. Anita goes away and indu leaves 7 days before the work is finished. Only geeta remains at work from beginning to end. In how many days was the whole work done?

Answer 1

In one day :

Anita = 1/18

Indu = 1/27

Geeta = 1/36

Total work done = 1/18 + 1/27 + 1/36 = 13/108

In four days :

4 × 13/108 = 13/27

Remaining work :

27/27 - 13/27 = 14/27

Indu + Geeta = 1/36 + 1/27 = 7/108

The time the should take to complete 14/27

14/27 × 108/7 = 8 days

But Indu leaves 7 days earlier.

In one day they do = 7/108

Remaining work:

14/27 - 7/108 = 49/108

Geera does 1/36 in a day.

Days he will take to finish 49/108

49/108 × 36/1 = 16 and 1/3 days

Total days taken to complete the work :

16  1/3 + 1 + 4 = 21$\frac{1}{3}$ days