Question

Alyn drives 20.4 miles in 17 minutes.

He passes a sign which gives the speed limit as 60 mph.
By how much, in mph, did Alyn's average speed exceed the speed limit?

Answer 1

• 12 mph

Explanation:

Speed = distance/time

• Distance = 20.4 miles
• Time = 17 minutes = 17*1/60 hours = 17/60 hours

Speed is:

• 20.4 : 17/60 =
• 20.4*60/17 =
• 72 mph

Alyn exceeded the limit by:

• 72 - 60 = 12 mph