McGraw Hill Integrated II, 2012
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McGraw Hill Integrated II, 2012 View details
1. Circles and Circumference
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Exercise 23 Page 720

Recall that the circumference of a circle is the product of its diameter and pi.

Radius: 13 inches
Circumference: 81.68 inches

Practice makes perfect

We are given that a bicycle has tires with a diameter of 26 inches. We have been asked to evaluate the radius r and the circumference of a tire. First let's recall that the radius is the half of the diameter. r=1/2* 26=13This means that the radius of a tire is 13 inches. Next, let's recall the formula for the circumference of a circle. C=Ï€ d By substituting 26 for d into the above formula we can find the circumference of a tire. We will round the result to the nearest hundredth.

C=Ï€ d
C=Ï€ ( 26)
C=81.6814...
C≈ 81.68

The circumference of a tire is approximately 81.68 inches.