The average speed is 1.54 miles per hour.
As we know that,
Average speed [tex]=\frac{Distance}{time}[/tex]
Given that Timmy and Sarah travel 5 miles in three hours and 15 minutes.
Time [tex]=3+\frac{15}{60} =\frac{13}{4}hours[/tex]
Average speed [tex]=5\div \frac{13}{4} =5*\frac{4}{13}=1.54 miles/hour[/tex]
Thus, The average speed is 1.54 miles per hour.
Learn more:
https://brainly.com/question/4931057
