Question 586411: if sammy can mow a lawn in 3 hours and laura can mow the same lawn in 4 hours, how long will it take them if they work together? Answer by nerdybill(7384) (Show Source):
You can put this solution on YOUR website! if sammy can mow a lawn in 3 hours and laura can mow the same lawn in 4 hours, how long will it take them if they work together?
Let x = time (hours) it takes together
then
x(1/3 + 1/4) = 1
x(4 + 3) = 12
x(7) = 12
x = 12/7
x = 1 hour and 43 minutes