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

Question

(1 point)
O 79 square mm
O 314 square mm
O 78.5 square mm
O 15.7 square mm

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. Since the diameter is 10 millimeters, the radius \( r \) is:

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

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

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

Therefore, the estimated area of the circle is 78.5 square mm.

So the correct answer is:

O 78.5 square mm.