Question
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.
(1 point)
O 79 square mm
O 314 square mm
O 78.5 square mm
O 15.7 square mm
(1 point)
O 79 square mm
O 314 square mm
O 78.5 square mm
O 15.7 square mm
Answers
GPT-4o mini
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**.
\[
\text{Area} = \pi r^2
\]
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**.