Question

A and b can together do a work in 8days. b alone can do the same work in 12days.

Answer 1

A and B together take 8 days [ Here ‘A’ and ‘B’ refers to the work done by ‘A’ and ‘B’] .

A takes 12 days .

So,

Let the work done by A ( in 1 day ) be one -twelfth(1/12) of the work done ..

so,

in 8 days =

= 8/12

So.. now we can say that A has done 1/8 of the work ..and B has done 1/B of the work .

1/A + 1/B = 1/12 [Here B refers to number days taken by B to do the work ]

1/8+ 1/B = 1/12

1/B = 1/24

[ We equate the denominators as the numerators are equal ]

No of days B takes to complete the work = 24 days ..