What is the area of a circle with a diameter of 10 millimeters? Estimate the area to the tenths place using 3.14 for π

Question

.(1 point)
Responses

78.5 square mm
78.5 square mm

314 square mm
314 square mm

15.7 square mm
15.7 square mm

79 square mm

Answer 1

To calculate 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 a diameter of 10 millimeters, the radius is:

\[ r = \frac{10}{2} = 5 \text{ millimeters} \]

Now, substituting for the radius in the area formula using \( \pi \approx 3.14 \):

\[ \text{Area} = 3.14 \times (5^2) = 3.14 \times 25 = 78.5 \text{ square mm} \]

So, the area of the circle is 78.5 square mm.

The correct response is:

78.5 square mm.