Question

A and b can finish a job in 15 days if a alone can finish the job in 25 days in how many days can be alone finish the job

Answer 1

Answer:

A can do the work in 20 days. Therefore, work done by A in one day = 1/20.

Let B can do the work in x days. Therefore, work done by B in one day = 1/x.

Now, if both of them work together, then work done by them in one day = 1/20 + 1/x

It is being given that when they work together, work is completed in 15 days.

Thus, 15 (1/20 + 1/x) = 1.

=> 15 ( x + 20 )/ 20x = 1

=> 15x + 300 = 20x

=> 5x = 300

=> x = 60.