SOLUTION: the distance from philadelphia to sea isle cit is 100 miles, a car was driven this distance using tires with a radius of 14 inches. how many revolutions of each tire occurred on th

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Question 100478: the distance from philadelphia to sea isle cit is 100 miles, a car was driven this distance using tires with a radius of 14 inches. how many revolutions of each tire occurred on the trip?
thank you so much for the help
Answer by doukungfoo(195) (Show Source):
You can put this solution on YOUR website!
First we must find the circumference of the tire.
Since a tire is a circle we can use the formula for circumference of a circle to find the circumference of the tire.
circumference equals diameter times

NOTE: since is an irrational number 3.14159265358979323846 (this is just a small portion of it). is commonly rounded to 3.14 for use in solving problems. This is the value we will use for

Now our formula for circumference require that we know the diameter. We are not given the diameter of the tire, but we are given the radius. The radius of a circle is equal to 1/2 the diameter. So to find diameter just multiply the radius by 2.

14*2=28

Now we have everything we need to find the circumference of the tire.

Ok so now we have found that the circumference of the tire is 87.92 inches.
But so what you might say, what good is that? Well this tells us that everytime the tire makes a complete revolution it travels 87.92 inches.
Now we can divide 87.92 inches into 100 miles to find out how many revolutions the tire made on the trip.
But first we need to convert 100 mile into inches.
1 mile = 5280 feet = 63360 inches
So how many inches in 100 miles
63360*100 = 6336000 inches
So finally divide 6336000 by 87.92
6336000/87.92 = 72065.5141 revolutions for each tire.