Question

A can do a piece of work in 15 days and B alone can do it in 10 days. B works at it for 5 days and then leaves. A alone can finish the remaining work in
(a) 6 days
(b) 5 days
(c) 8.5 days
(d) 7.5 days

Answer 1

(c) 8.5. is the correct answer

Answer 2

B's 5 days work =  

110∗5=12

Remaining work =1−12

=12A

can finish work =15∗12=7.5days

so option D