Which of the following uses the correct formula to find the approximate circumference of a circle that has a radius of 12? Use 3.14 for π and express your answer to the hundredths place.(1 point)

The correct formula to find the approximate circumference of a circle is C = 2πr.

Using this formula, the approximate circumference of a circle with a radius of 12 is:
C = 2 * 3.14 * 12 = 75.36

Therefore, none of the following options are correct.

Which of the following uses the correct formula to find the approximate circumference of a circle that has a radius of 450?(1 point)

Which of the following uses the correct formula to find the approximate circumference of a circle that has a radius of 450?(1 point)

Responses

C≈3.14⋅450÷2
upper C approximately equals 3.14 times 450 divided by 2

C≈3.14⋅150
upper C approximately equals 3.14 times 150

C≈3.14⋅4502
upper C approximately equals 3.14 times 450 squared

C≈2⋅3.14⋅450

The correct formula to find the approximate circumference of a circle is C = 2πr.

Using this formula, the approximate circumference of a circle with a radius of 450 is:
C = 2 * 3.14 * 450 = 2826

Therefore, the correct option is:
C≈2⋅3.14⋅450

Which formula correctly describes the proportional relationship between the circumference of a circle and the diameter?(1 point)

Responses

Cd=π
Start Fraction upper C over d End Fraction equals pi

π=dC
pi equals Start Fraction d over upper C

A=πr2
upper A equals pi r squared

C=πd
upper C equals Start Fraction pi over d End Fraction

The correct formula that describes the proportional relationship between the circumference of a circle and the diameter is:

C = πd

This means that the circumference (C) is equal to the diameter (d) multiplied by pi (π).

Therefore, the correct option is:
C=πd

Use the correct formula to find the area of a circle if the diameter is 21 mi. Round to the nearest hundredths place. Use 3.14 for π .(1 point)

Responses

1,384.74 mi.2
1,384.74 mi squared

65.94 mi.2
65.94 mi squared

131.88 mi.2
131.88 mi squared

346.19 mi.2

The correct formula to find the area of a circle is A = πr^2, where r is the radius of the circle.

Given that the diameter is 21 mi, we can find the radius by dividing the diameter by 2:
r = 21 mi / 2 = 10.5 mi

Using the formula and approximating π to 3.14, the area of the circle is:
A = 3.14 * (10.5 mi)^2 = 3.14 * 110.25 mi^2 = 345.915 mi^2

Rounding to the nearest hundredths place, the area is approximately 345.91 mi^2.

Therefore, the correct option is:
346.19 mi.2

The correct formula for finding the area of a circle?

The correct formula for finding the area of a circle is:

A = πr^2

Where A represents the area of the circle and r represents the radius.