#### Answer

Interpreting the solution in terms of how we defined $x$ and $y$ in part (a),
Ashley spends $\displaystyle \frac{80}{3}=26\frac{2}{3}$ minutes on the stair machine, and
$\displaystyle \frac{40}{3}=13\frac{1}{3}$ minutes on the rowing machine
(This is a total of 40 minutes of exercise.)

#### Work Step by Step

Given above.