Question

A can complete a work in 30 days Both A and B can complete the same work in 20 days they work together for 10 days and then A goes away In how many dyas will B finish the work​

Answer 1

A takes 30 days to complete - 1 work.

So, A takes 1 day to complete - 1/30th of the work.

B takes 20 days to complete - 1 work.

So,

B takes 1 day to complete 1/20th of the work

So A and B together do in 1 day - 1/30+ 1/20= 5/60th of the work.

If 5/60th of the work is done in - 1 day

Then 1 work is done in - 1/ 5/60 days= 60/5 days=12 days.

So,

A+B does the work in 12 days.

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