Question

Mohan takes 7days more than john to do a certain piece of work . Together they can do it in 12 days. Haw many days mohan take to do that work

Answer 1

Answer:

Step-by-step explanation:Let the time taken by Ravi to finish the work be 'x' days, then Mohan takes 'x-8' days.

As Mohan and Ravi together can finish the work in 7.5 or 15/2 days, their 1 day work=2/15.

So, 1/x + 1/(x-8)= 2/15

(x-8+x)/[x(x-8)] =2/15

x^2 -23x+60 =0

(x-3)(x-20)=0

as x can't be 3, x=20,

Hope it's helps you