Question

A&b can do work in 12 days,b alone can finish it in 28 days.how mamy days a alone finsh

Answer 1

in this problem simple way to find answers

( A + B ) - B = A

one days work of a and b together is

1
--
12

and

b one day work is

1/28

now a = 1/12 - 1/28

= (28 - 12)/( 12 × 28 )

1/21

a can do work in 21 days

Answer 2

Answer is 21 days.

hope it helps........

purple you......