Billy and Ellie ride their bikes from their neighborhood to their school 7.25 kilometers away. At the end, Billy races ahead and gets there 3 minutes before Ellie. What is the difference in their average speed if it took Ellie 29 minutes to get to school?

Question

Billy and Ellie ride their bikes from their neighborhood to their school 7.25 kilometers away. At the end, Billy races ahead and gets there 3 minutes before Ellie.  What is the difference in their average speed if it took Ellie 29 minutes to get to school?

oobleck · Answer

Ellie: 7.25km/29min = 0.25 km/min Billy: 7.25km/26min = 0.279 km/min Billy-Ellie = 0.029 km/min