Question

10 )There are roadworks on a motorway.

The average speed limit is 50 mph.
A car travels a distance of 18 miles in 24 minutes.
Is the average speed of the car less than 50 mph?
Show why you think this.

(3)

Answer 1

yes the average speed of the car is less than 50 mph

Explanation:

average speed = total distance / total time

total distance covered = 18 miles

total time taken = 24 minutes = 24/60 = .4 hours

average speed = 18/.4 = 45 mph

thus, yes the calculated average speed of the car is less than the limit of 50 mph

Answer 2

the average speed of the car is less than 50mph

Explanation:

1. First lets calculate the speed of this car using the formula

Speed = distance/time

therefore our

speed = 18miles/24min or

speed= 3miles/4mins (divide by 6 to simplify)

2. Now to find the speed per hour we just need to multiply by 15

speed = 45miles/60mins or

speed = 45mph (miles per hour as 60mins = 1 hour)

3. Therefore the average speed of the car is less than 50mph