Question

A is 3 times as efficient as b and is able to finish the job in 60 days less

Answer 1

Let B take 3x days to complete work alone.

Then, A takes x days to complete work alone.

Given 3x - x = 10

=> x = 5

=> A alone 5 days & B alone 15 days.

A & B together will take :

(5 x 15)/(5+15)=75/20 = 3 3/4 days.