Question

A and B can do a piece of work in 20 days. B alone can do the work in 15 days. How many days A will take to do the work. mention the formula.

Answer 1

Answer:

When B alone takes only 15 days then why working with A he will take 20 days

either question is wrong or A destroy the work rather than doing work

so A takes 60 days to destroy the work

Step-by-step explanation:

1/A   = 1/(A+B)  - 1/B

1/A =  1/20 - 1/15

1/A = (1/60) *(3-4)

1/A = -1/60

A = -60 Days

so either question is wrong or A destroy the work rather than doing work

so A takes 60 days to destroy the work