Question

The distance between Chicago and Cleveland is

354 miles. If a person leaves Chicago at 9:50
AM. Central Time and arrives in Cleveland at
5:30 PM the same day Eastern Time, at what
average speed, to the nearest mile, does he
travel?

A)46MPH
B)50MPH
C)53MPH
D)55MPH​

Answer 1

The average speed on this trip was 46.15 mph. The correct option is A.

Explanation:

In order to calculate the average speed, we need to apply the following formula:

`v_(avg) = \frac{\text{distance}}{\text{time}}`

We were given the distance between the two cities in miles, therefore we can directly apply it to the expression. Although the time was given in the hh:mm 12 h format and we need a diference in hours, so we will convert that as shown below:

`\text{time departure} = 9 + (50)/(60) = 9.83 \text{ h}`

`\text{time arrival} = 12 + 5 + (30)/(60) = 17.5`

The elapsed time of the trip is the difference between these:

`\text{time} = 17.5 - 9.83 = 7.67 \text{ h}`

We can now apply it to the formula:

`v_(avg) = (354)/(7.67) = 46.15 \text{ mph}`

The average speed on this trip was 46.15 mph. The correct option is A.