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)
Responses
452.16
452.16
18.84
18.84
75.36
75.36
37.68
The correct formula to find the approximate circumference of a circle is C = 2πr, where r is the radius of the circle.
Using this formula, the approximate circumference of a circle with a radius of 12 would be:
C = 2π(12)
C = 24π
Since the question instructs us to use 3.14 for π, we can substitute it into the formula:
C = 24(3.14)
C = 75.36
Therefore, the correct answer is 75.36.
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⋅4502
upper C approximately equals 3.14 times 450 squared
C≈3.14⋅450÷2
upper C approximately equals 3.14 times 450 divided by 2
C≈2⋅3.14⋅450
upper C approximately equals 2 times 3.14 times 450
C≈3.14⋅150
The correct formula to find the circumference of a circle is C = 2πr, where r is the radius of the circle.
Using this formula, the approximate circumference of a circle with a radius of 450 would be:
C = 2π(450)
Since the question instructs us to use 3.14 for π, we can substitute it into the formula:
C = 2(3.14)(450)
C = 2(1413)
C = 2826
Therefore, the correct answer 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
A=πr2
upper A equals pi r squared
C=πd
upper C equals Start Fraction pi over d End Fraction
Cd=π
Start Fraction upper C over d End Fraction equals pi
π=dC
The correct formula that describes the proportional relationship between the circumference of a circle and the diameter is:
C = πd
Here, C represents the circumference and d represents the diameter. This formula states that the circumference of a circle is equal to π (pi) multiplied by the diameter.
Therefore, the correct answer 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
346.19 mi.2
346.19 mi squared
131.88 mi.2
131.88 mi squared
1,384.74 mi.2
1,384.74 mi squared
65.94 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, the radius can be found by dividing the diameter by 2:
r = 21 mi / 2 = 10.5 mi
Now, substituting the value of the radius into the formula and using 3.14 for π:
A = π(10.5 mi)^2
A = 3.14 * (10.5 mi)^2
A = 3.14 * 110.25 mi^2
A ≈ 346.19 mi^2 (rounded to the nearest hundredth)
Therefore, the correct answer is 346.19 mi^2.
Which of the following is the correct formula for finding the area of a circle?(1 point)
Responses
A=2πr
upper A equals 2 pi r
A=πr2
upper A equals pi r squared
A=C2÷4πA=πd2
upper A equals upper C squared divided by 4 pi upper A equals pi d squared
A=πd
The correct formula for finding the area of a circle is:
A = πr^2
Here, A represents the area and r represents the radius of the circle. This formula states that the area of a circle is equal to π (pi) multiplied by the square of the radius.
Therefore, the correct answer is A = πr^2.