Chapter 0.7, Problem 11E

To determine

To calculate: The circumference of the given circle to the nearest tenth,

  

Answer to Problem 11E

The circumference of the circle is $\text{31}\text{.4 in}\text{.}$ .

Explanation of Solution

Given information:

The figure is provided below,

  

Formula used:

Circumference $\left(C\right)$ of a circle with radius r units is denoted by $C=2\pi r$ .

Calculation:

Consider the provided figure,

  

In the above figure the circle has the diameter of 10 inches,

Since, radius is half of diameter,

So, radius of circle is calculated as,

  $\begin{array}{c}r=\frac{\text{10}}{\text{2}}\text{in}.\\ =\text{5 in}\text{.}\end{array}$

Recall that circumference $\left(C\right)$ of a circle with radius r units is denoted by $C=2\pi r$ .

Apply it,

  $\begin{array}{c}C=2\cdot \frac{22}{7}\cdot 5\\ =31.428\text{ in}\text{.}\end{array}$

Rounding off to the nearest tenth,

  $C=31.4\text{ in}\text{.}$

Thus, the circumference of the circle is $\text{31}\text{.4 in}\text{.}$ .