Question

Paru and seenu can do work in 8 days seenu and raj can do the same work in 12 days paru,seenu and raj together cam finish it in 6 days in how many days will paru and raj together complete the work

Answer 1

Let days taken by each of Paru, Seenu and Raj be p, s and r resp.

So, time taken by Paru and Seenu to do work = 8 days

in 1 day, they will do = 1/8 work

So, 1/p + 1/s = 1/8.....(1)

Similarly, we can write

1/s + 1/r = 1/12.....(2)

and

1/p + 1/s + 1/r = 1/6....(3)

Putting (1) in (3), we get

1/8 + 1/r = 1/6

1/r = 1/6 - 1/8

1/r = 4/24 - 3/24 = 1/24

Putting (2) in (3), we get

1/p + 1/12 = 1/6

1/p = 1/6 - 1/12

1/p = 2/12 - 1/12 = 1/12

So, 1/p + 1/r = 1/24 + 1/12

= 1/24 + 2/24 = 3/24 = 1/8

So, Paru and Raj will do the work in 8 days