Question

A can do a work in 10 days & B can do it in 15 days, if they work together for 5 days, then how many days work will be finished

Answer 1

Work done by A in 1 day = 1/10
Work done by B in 1 day = 1/15
Therefore, work done by them together in one day...
--> 1/10 + 1/15
--> 25/150
--> 1/6
And that means.. they will complete the work together in 6 days