Inactive Tutor answered • 02/24/13
Tutor
New to Wyzant
Since Jessie can weed a garden in 30 minutes, her rate is 1/j of the garden per minute, which equals 1/30th of the garden per minute. Norton's rate is 1/n of the garden per minute. Working together, their rate is:
(1/j)+(1/n)=(1/20) of the garden per minute
(1/30)+(1/n)=(1/20) of the garden per minute
We want to solve for n so subtract 1/30 from boths sides:
(1/n)=(3/60)-(2/60) of the garden per minute
(1/n)=(1/60) of the garden per minute
So since Norton's rate is 1/n which equals 1/60, this means that he can weed 1/60th of the garden per minute. Which means that it would take him 60 minutes, or 1 hour, to finish the garden by himself.
