Problem: On an auto trip, the distance read from the instrument panel was miles. With snow tires on for the return trip over the same route, the reading was miles. Find, to the nearest hundredth of an inch, the increase in radius of the wheels if the original radius was inches.
Answer Choices:
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Solution:
The distances read are inversely proportional to the radii of the tires so that
where is the increase. Hence the increase inches.