Question

Charlotte walks home from school every day at a rate of

4 miles per hour. It takes her 30-minutes to reach
home. Her brother, Noah, runs home from the same
school every day at a rate of 6 miles per hour. How
many fewer minutes does it take Noah than Charlotte
to reach home from school each day? Be sure to
SHOW your WORK!

Answer 1

It takes 10 fewer minutes for Noah than for Charlotte to home from school each day.

Explanation:

We use the following relation to solve this question:

`v = (d)/(t)`

In which v is the velocity, d is the distance, and t is the time.

Finding the distance:

Charlotte walks home from school every day at a rate of 4 miles per hour. It takes her 30-minutes to reach home.

This means that
`t = 0.5, v = 4`. Time is 0.5 because as the velocity is in miles per hour, the time has to be in hours. We use this to find d.

`v = (d)/(t)`

`4 = (d)/(0.5)`

`d = 4*0.5 = 2`

The distance is of 2 miles.

Her brother, Noah, runs home from the same school every day at a rate of 6 miles per hour.

We have to find t, in hours, for which
`v = 6, d = 2`. So

`v = (d)/(t)`

`6 = (2)/(t)`

`6t = 2`

`t = (1)/(3)`

A third of an hour. In minutes, this is a third of 60, that is 60/3 = 20 minutes.

How many fewer minutes does it take Noah than Charlotte to reach home from school each day?

Noah: 20 minutes

Charlotte: 30 minutes

30 - 20 = 10

It takes 10 fewer minutes for Noah than for Charlotte to home from school each day.