Betty goes out from her home for a stroll in the park. We know that she takes a rest $5$ minutes each $85\,m$. If she walks with a constant speed of $15\frac{m}{min}$ and she takes $98$ minutes to get back to her home. How long does she took rest?

The alternatives in book are as follows:

$\begin{array}{ll}

1.&\textrm{43 min}\\

2.&\textrm{45 min}\\

3.&\textrm{35 min}\\

4.&\textrm{40 min}\\

\end{array}$

How can I find the time she has rested in this given context?

What I attempted to do is to find the total time of minutes she has rested by adding the resting time and the time she was walked.

Assuming that the length between her home and all the stroll she has made is $x$:

Then this would be:

$x\left(\frac{1\,min}{15\,m}\right)+x\left(\frac{5\,min}{85\,m}\right)=98$

But this didn't result in an answer near to any of the alternatives. What could be wrong? Can someone help me here?

The answer my book states is $45\,min$.