Petra walks his dog once a day. Most days when Petra walks his dog, he takes a route that is \(3 \frac{1}{2}\) km long. When it is raining, he does a shorter walk which is only \(2\) km long.
One week it rained for \(3\) days and did not rain on the other \(4\) days. How far did Petra walk his dog that week?
Themes: Geometry & Measurement, Number Sense