Week 317 (6th October 2023)

Two friends have become quite competitive with their running.  

Jolie runs for 15 minutes at an average speed of 6 miles per hour.  

She then runs for 40 minutes at an average speed of 9 miles per hour.  

It takes Alfie 45 minutes to run the same total distance that Jolie runs.  

Work out Alfie’s average speed.  

Give your answer in miles per hour. 


speed = distance/time, if we want our answer in mph distance must be in miles and time in hours.  

We need to find the total distance Jolie ran in 2 parts since she changed speed.  

6 = distance/0.25, multiply both sides by 0.25 to find that distance = 1.5miles 

9 = distance/0.67, multiple both sides by 0.67 to find that distance = 6miles 

Now we can find the speed of Alfie:  

speed = 7.5/0.75 = 10mph