Question

When Ruby works out, she spends 2 minutes stretching for every 15 minutes of exercise. If Ruby spends 15 minutes stretching, how long did she spend exercising?

Answer 1

The ratio of time spend for stretching to time spend for exercise remain same.

Equate the ratio of time spend for stretching to time spend for exercise in both cases.

`\begin{gathered} (2)/(15)=(15)/(x) \\ x=(15\cdot15)/(2) \\ =112.5 \end{gathered}`

So Ruby spend 112 and a half minute to spend 15 minutes in stretching.

So answer is 112.5 min or

`112(1)/(2)`