Four tires and a spare - Math Central

HOME

Math Central

Quandaries & Queries

Question from stacey, a parent:

a car is driven 40,000 miles using four tires and a spare. the tires are
rotated so that each tire travels the same number of miles. What is the
number of miles traveled by each tire??
HINT: the answer is not 8,000 miles each.

Hi Stacey,

If there were only 4 tires and no spare then each tire would be on the car all the time so the number of miles of wear on each tire would be 40,000 miles. But there are 5 tires so each tire is used four fifths of the time.

Penny

Math Central is supported by the University of Regina and The Pacific Institute for the Mathematical Sciences.