Janet goes for a run and is out for an hour and 20 minutes. She knows she runs at about 4 mph. How many miles did she run, approximately?

To solve problems about travel time: $8686_w187_h14.png$.
We figure out which variable we want to solve for and isolate it.
In this case, we are trying to figure out the distance, so we can use the equation as it is. However, we must convert the minutes to hours: 1 hour and 20 minutes
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1 hour + 0.3 hours = 1.3 hours
Then we plug in our numbers:
$8686_w187_h14.png$
4 × 1.3 = 5.2