Use the correct formula to find the area of a circle if the diameter is 21 mi. Round to the nearest hundredths place. Use 3.14 for π . Responses: 1,384.74 mi.2 1,384.74 mi squared 346.19 mi.2 346.19 mi squared 65.94 mi.2 65.94 mi squared 131.88 mi.2

Answer 1

To find the area of a circle, you can use the formula:

$$\text{Area}=\pi r^2$$

where $r$ is the radius of the circle. The radius is half of the diameter.

Given that the diameter is 21 mi, the radius $r$ is:

$$r=\frac{21}{2}=10.5\text{ mi}$$

Now, we can substitute the radius into the area formula:

$$\text{Area}=3.14\times (10.5{)}^2$$

Calculating $(10.5{)}^2$:

$$(10.5{)}^2=110.25$$

Now plug that back into the area formula:

$$\text{Area}=3.14\times 110.25\approx 346.19{\text{ mi}}^2$$

Rounding to the nearest hundredths place gives:

$$\text{Area}\approx 346.19{\text{ mi}}^2$$

Therefore, the correct response is 346.19 mi squared.