Question

'A' dose a work in 10 days and 'B' dose the same work in 15 bays. in how many days they together will do the same work?

Answer 1

Total work =1
A takes 10 days. So, in one day, he completes 1/10th of his work.
Similarly, B completes 1/15 of its work.
If they work together, they will complete (1/10+1/15) work.
Let the time required be x days.
Equation will be x*(1/10+1/15)=1
x×(5/30)=1
x=30/5
x=6