Question

A and B can complete a work in 15 days and 10 days respectively. They started doing the work together but after 2 days B had to leave, and A alone completed the remaining work. In how many days will the whole work get completed?

(a) 8
(b) 10
(c) 12
(d) 15

Answer 1

A and B can complete the work together in 16 days.

Step-by-step explanation:

Let's find out the work done by A and B individually in one day.

If A completes the work in 15 days, it means A can complete 1/15th of the work in one day.

In the same way, B can complete 1/10th of the work in one day.

When A and B work together for 2 days, they complete (1/15 + 1/10) * 2 = 1/15 of the work.

So, the remaining work is 1 - 1/15 = 14/15.

Since A can complete 1/15th of the work in one day, A will complete the remaining work in (14/15) * 15 = 14 days.

So, the whole work will get completed in 2 + 14 = 16 days.