Question

Find the area of the circle using the given data. 3. 1. Radius = 12 cm. 2. Diameter = 30 m. Diameter = 100 dm. 4. Radius = 24 cm. Diameter = 2.8 m. 6. Radius = 40 mm. 7. Radius = 65 inches 8. Diameter = 48 yards 9. Radius = 17 feet 5. 10. Diameter = 75 units​

Answer 1

To find the area of a circle, use the formula A = πr2. The area can be calculated using different values for the radius or diameter. The results are rounded to the appropriate significant figures.

Step-by-step explanation:

The formula to find the area of a circle is A = πr2. The area can be calculated using the given data as follows:

1. When the radius is 12 cm, A = 3.1415927... x (12 cm)2 = 452.38934 cm2 ≈ 452.4 cm2.
2. When the diameter is 30 m, the radius is half of the diameter, so it is 15 m. A = 3.1415927... x (15 m)2 = 706.858347 m2 ≈ 706.9 m2.
3. When the diameter is 100 dm, the radius is half of the diameter, so it is 50 dm. A = 3.1415927... x (50 dm)2 = 7853.981634 dm2 ≈ 7854 dm2.
4. When the radius is 24 cm, A = 3.1415927... x (24 cm)2 = 1810.97374 cm2 ≈ 1811 cm2.
5. When the diameter is 2.8 m, the radius is half of the diameter, so it is 1.4 m. A = 3.1415927... x (1.4 m)2 = 6.15752051 m2 ≈ 6.2 m2.
6. When the radius is 40 mm, A = 3.1415927... x (40 mm)2 = 5026.54825 mm2 ≈ 5026.5 mm2.
7. When the radius is 65 inches, A = 3.1415927... x (65 inches)2 = 13273.27714 inches2 ≈ 13273.3 inches2.
8. When the diameter is 48 yards, the radius is half of the diameter, so it is 24 yards. A = 3.1415927... x (24 yards)2 = 5421.59265 yards2 ≈ 5421.6 yards2.
9. When the radius is 17 feet, A = 3.1415927... x (17 feet)2 = 908.269375 feet2 ≈ 908.3 feet2.
10. When the diameter is 75 units, the radius is half of the diameter, so it is 37.5 units. A = 3.1415927... x (37.5 units)2 = 4416.990876 units2 ≈ 4417 units2.