Q11. - Algebra 1

Question

Find the circumference of each circle. Round to the nearest tenth.

Step-by-Step Solution

Answer

The circumference of the circle is 31.4 in.

Step 1. Given information.

The circle has a diameter of 10 inches.

Step 2. Circumference of the circle.

The circumference of a circle with radius r units is denoted by $C=2\pi r$.

Step 3. Calculations.

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

Since, the radius is half of the diameter,

So, the radius of a circle is calculated as,

$$\begin{gathered} r=\frac{10}{2}\mathrm{in}. \\ =5\mathrm{in}. \end{gathered}$$

The circumference of a circle

$$\begin{gathered} C=2\pi r \\ =2·\frac{22}{7}·5 \\ =31.428\mathrm{in}. \end{gathered}$$ 

Rounding off to the nearest tenth,

$C=31.4\mathrm{in}.$

Thus, the circumference of the circle is 31.4 in.