Question

You are going to run at a constant speed of 7.5 miles per hour for 45 minutes. You calculate the distance you will run. What mistake did you make in your calculation? [Use the formula S=dt.]

Answer 1

A

Explanation:

i got it right

Answer 2

We are given that:
speed = 7.5 miles/hour
time = 45 minutes

We can note that the units of time are not the same (hour for speed and minutes for time that you will run). Therefore, the most common mistake that would be done in this case is to calculate the distance without converting the units to be consistent with one another.

Wrong solution:
speed = 7.5 miles/hour
time = 45 minutes
Distance = 7.5 * 45 = 337.5 miles

Correct solution:
speed = 7.5 miles/hour
time = 45 minutes = 0.75 hour
Distance = 7.5 * 0.75 = 5.625 miles

Hope this helps :)