Question

A and B together can finish a piece of work in 12 days. If A alone can finish the same
work in 20days, in how many days B alone can finish it?​

Answer 1

A and B finish the work together = 12days

A can finish work alone = 20 days

A one day work = 1/20 days

let B do work be x days

B one day work = 1/x days

A and B together one day work = 1/12

according to question

1/x + 1/20 = 1/12

1/x = 1/12 - 1/20

1/x= 8/240

x =30 days

B complete his work = 30 days

Answer 2

Answer

N can complete the work in 30 days

Solution

A and B combined can do the work in 1 day = 1/12

A can do work in 1 day = 1/20

So , B along can do the work will

$\frac{1}{12} - \frac{1}{20}$

$= > \frac{2}{60}$

$= > \frac{1}{30}$

So A can do work in 1 day = 1/30

then A can do total work = in 30 days

hope it helps