Rowena is able to mow $\frac{2}{5}$ of a lawn in 18 minutes. If she began the job at 10:00 a.m., and mowed at this same constant rate, when did she finish mowing the entire lawn?
(A) 10:08 a.m.
(B) 11:30 a.m.
(C) 10:40 a.m.
(D) 10:25 a.m.
(E) 10:45 a.m.

## Part B: Each correct answer is worth 6.
Rowena is able to mow $\frac{2}{5}$ of a lawn in 18 minutes. If she began the job at 10:00 a.m., and mowed at this same constant rate, when did she finish mowing the entire lawn?
(A) 10:08 a.m.
(B) 11:30 a.m.
(C) 10:40 a.m.
(D) 10:25 a.m.
(E) 10:45 a.m.

## Solution

Since Rowena can mow $\frac{2}{5}$ of the lawn in 18 minutes, she can mow $\frac{1}{5}$ of the lawn in 9 minutes. This tells us that it takes her $5 \times 9=45$ minutes to mow the whole lawn. So if she starts at 10:00 a.m., she finishes at 10:45 a.m.

## Part B