Question

Niamh was driving back home following a business trip.

She looked at her Sat Nav at 17:30
Time: 17:30
Distance: 143 miles
Niamh arrived home at 19:42
Work out the average speed of the car, in mph, from 17:30 to 19:42
You need to show all your working
:)​

Answer 1

65 mph

Explanation:
To calculate the average speed of Niamh's car, we need to use the formula:

Average speed = Total distance ÷ Total time

First, we need to calculate the total time elapsed from 17:30 to 19:42:

Total time = 19:42 - 17:30 = 2 hours and 12 minutes

To convert the minutes to decimal form, we divide by 60:

2 hours and 12 minutes = 2 + (12 ÷ 60) = 2.2 hours

Now we can calculate the average speed:

Average speed = Total distance ÷ Total time

Average speed = 143 miles ÷ 2.2 hours

Average speed = 65 mph

Therefore, the average speed of Niamh's car from 17:30 to 19:42 was 65 mph.