Problema Solution
A boy can mow the lawn in 45 minutes and his friend can mow the lawn in 30 minutes. If they work together, how many minutes will it take them to mow the lawn?
Answer provided by our tutors
Efficiency of boy = 1/45
Efficiency of his friend = 1/30
So,
If there combined efficiency is x then
1/x = 1/45 + 1/30 = 75/(45*30) = 1/18
x = 18.
Therefore,
They will take together 18 minutes to mow the lawn.