Question

5 The tires on a truck have been changed such that the ratio of the circunference or the new line to that of theactory installed tire is 1.2. The speed limit is 55 mph. What number on your speedometer must you stay at orbelow if you do not wish to break the speed limit

Answer 1

For every circumference that the new tire does, the factory-installed tire will make 2.

The speedometer calculates the velocity using the number of revolutions.

So, with the new tire, the speedometer is going to say the half of the actual velocity. Therefore, you must stay at 27.5 (55/2=27.5) mph or below if you don't want to break the speed limit.

Answer: 55/2 mph = 27.5 mph