Question

Yesterday, Carmen went on a bike ride. Her average speed was 8 miles per hour. Today, she went on another ride, this time averaging 13 miles per hour. In the two days, she biked for a combined total time of 9 hours.
Let x be the number of hours she biked yesterday. Write an expression for the combined total number of miles she biked in the two days?

Answer 1

Answer: the expression for the combined total number of miles she biked in the two days is

117 - 5x miles

Step-by-step explanation:

Let x be the number of hours she biked yesterday.

In the two days, she biked for a combined total time of 9 hours. This means that the number of hours that she biked today is (9 - x) hours.

Distance = speed × time

Yesterday, Carmen went on a bike ride. Her average speed was 8 miles per hour. This means that the distance that she covered yesterday is 8x miles

Today, she went on another ride, this time averaging 13 miles per hour. This means that the distance that she covered today is 13(9 -x) miles.

An expression for the combined total number of miles she biked in the two days is

8x + 13(9 - x)

= 8x + 117 - 13x

= 117 - 5x