Question

A and b together can complete a work in 20 days. They started together but after 4 days a left the work. The remaining work was completed by b alone in 24 more days. In how many days can a complete the entire work alone ?

Answer 1

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Answer 2

Given :

A and b together can complete a work in 20 days. They started together but after 4 days a left the work. The remaining work was completed by b alone in 24 more days

To Find:

In how many days can a complete the entire work alone ?

Solution:

A and b together can complete a work in 20 days

A and b together can do a part of work in 1 day =$\frac{1}{20}$

A and b together can do a part of work in 4 days =$\frac{4}{20}$

Remaining work = $1 - \frac{4}{20}=\frac{16}{20}$

B complete $\frac{16}{20}$ part of work in days = 24

B can do complete work alone in days =$\frac{24}{\frac{16}{20}}=30$

B 's 1 day work = $\frac{1}{30}$

A's 1 day work =$\frac{1}{20}-\frac{1}{30}=\frac{1}{60}$

A can do complete work alone in 60 days