How Far Did Each Tire Travel?
Date: 01/01/2003 at 22:17:42 From: Linda Subject: A tire question A woman went on a 80,000 mile trip. By using her spare tire, she used all her tires (including the regular four) for equal distances. How far did each tire travel?
Date: 01/01/2003 at 22:47:35 From: Doctor Jeremiah Subject: Re: A tire question Hi Linda, Each tire must travel 4/5 of the distance, because there are 5 tires available and only 4 tires in use at a time. Just to simplify everything, let's say that we are going 100 miles. The first 20 miles we use tires 1, 2, 3, 4 The second 20 miles we use tires 1, 2, 3, 5 The third 20 miles we use tires 1, 2, 5, 4 The fourth 20 miles we use tires 1, 5, 3, 4 The fifth 20 miles we use tires 5, 2, 3, 4 Look at the number of times each tire goes 20 miles. Each tire is in exactly four of the five 20 mile trips, so each tire goes 4/5 of the total distance. - Doctor Jeremiah, The Math Forum http://mathforum.org/dr.math/
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