I don't know how to calculate this or how to even start it.

First convert the time to seconds. Then calcuilate average speed in miles per second by dividng the distance traveled (in miles) by time (in seconds). But since they want the answer in miles per hour you must multiply by a conversion factor. You should know that 1 hour equals 3600 seconds, so you can multiply your answer above by

\frac {3600\ s}{1\ Hr}

because that's like multiplying by 1. This converts the answer from miles per second to miles per hour. For example, you can convert 0.1 miles per second to the equivalent miles per hour like this:


0.1 \frac {miles} {s} = 0.1 \frac {miles} {s} \times \frac {3600 s}{1\ Hr} = 360 \frac {miles} {Hr}


Hope this helps - post back with your final answer and we'll check it for you.

A simple method is 5 Miles / 73 Seconds = 0.068 Miles per Second.
now 0.068 Miles per second x 60 Seconds = 4.08 Miles per Minute.
then 4.08 Miles per minute x 60 Minutes = 244.8 Miles per Hour.
On average it will travel 244.8 Miles per Hour.