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Jeremy travels from A to B at 2 minutes per mile and returns over the same route at 2 miles per minute. Find his average speed, in miles per hour, for the whole trip.
This is the first of several problems involving averages.
There are several steps required to solve this problem. It's important
to get through as many of them as you can.
First, you need to figure out how fast Jeremy was going on each part
of his trip, in common units. Probably the most sensible units are miles
per hour.
The next thing you might realize is that there's no indication of
either
how far the trip is, or else how long it took Jeremy to make it. So you
get to pick any distance you want (pick an easy one!), then calculate how
long it
takes Jeremy to go in each direction for this distance
(remember, distance = rate x time), and finally
calculate the average speed for the trip.
The last thing you have to do to complete the problem is show that
the average doesn't depend on the distance.
As always, be sure to explain the
work you did to arrive
at your answers!
So, how fast in mph is "2 minutes per mile"? How fast is "2 miles per
minute"?