Answered

A boy can do a piece of work in 15 days and his father can do it in 10 days.
How long will it take them to do the work together?

Sagot :

EngrBenamerviz
the answer to your question previously is ... 6 days ..
the solution is ... 
1/15 + 1/10 = 1/x
2x + 3x = 30
5x = 30
x = 6 days