A, B and C can do a work in 5 days, 10 days and 15 days respectively. They started together to do the work but after 2 days A and B left. C did the remaining work (in days)

First, let's find out how much work each person can do in a day.

1. A can finish the work in 5 days, so A can do 1/5 of the work in a day.
2. B can finish the work in 10 days, so B can do 1/10 of the work in a day.
3. C can finish the work in 15 days, so C can do 1/15 of the work in a day.

When they work together, they can do (1/5 + 1/10 + 1/15) of the work in a day. This simplifies to 1/2 of the work in a day.

So, in 2 days, they can do 2 * (1/2) = 1 work. This means the work is finished.

But the problem says that A and B left after 2 days. This means that only C was left to do the remaining work.

Since the work is already finished, there is no remaining work for C to do. So, C did 0 days of work.

First, let's find out how much work each person can do in a day.

1. A can finish the work in 5 days, so A can do 1/5 of the work in a day.
2. B can finish the work in 10 days, so B can do 1/10 of the work in a day.
3. C can finish the work in 15 days, so C can do 1/15 of the work in a day.

When they work together, they can do (1/5 + 1/10 + 1/15) of the work in a day. This simplifies to 1/2 of the work in a day.

So, in 2 days, A, B, and C together can do 2*(1/2) = 1 work. This means the work is completed.

But since A and B left after 2 days, the remaining work is 0. So, C did not have to do any more work. Therefore, C did the remaining work in 0 days.