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.
The area of a circle is given by the formula A = πr^2, where r is the radius of the circle.
Since the diameter is given as 10 millimeters, the radius is half of that, which is 5 millimeters.
Substituting the value of the radius into the formula, we have A = 3.14 * 5^2 = 3.14 * 25 = 78.5
Therefore, the estimated area of the circle is 78.5 square millimeters.
To find the area of a circle, you can use the formula A = πr^2, where A is the area and r is the radius.
1. Start by finding the radius. The radius is half the diameter, so divide the diameter by 2:
r = 10 mm / 2 = 5 mm.
2. Square the radius:
r^2 = 5 mm * 5 mm = 25 mm^2.
3. Multiply the squared radius by π (approximately 3.14):
A = 3.14 * 25 mm^2.
A ≈ 78.5 mm^2.
So, the estimated area of the circle is 78.5 square millimeters, rounded to the tenths place.