What is the approximate circumference of a circle that has a radius of 63? Use 3.14 for π

and express your answer to the hundredths place.(1 point)

What is the approximate circumference of a circle that has a diameter of 20? Use 3.14 for π
and express your answer to the tenths place.(1 point)

A circle has an approximate circumference of 574 meters
. What is the circle’s diameter, rounded to the nearest tenth? Use 3.14
for π
. (1 point)
meters

If a circle has a radius of 38 inches
, what is its approximate circumference to the nearest hundredths? Use 3.14
for π
.(1 point)
inches

The radius of a circle is 75 mm. What is the approximate area of the circle? Write your answer to the tenths place. Use 3.14 for π
.(1 point)
mm2

2 answers

Let's solve each part of your question one at a time.

  1. Circumference of a circle with radius 63:

    The formula for circumference \(C\) is: \[ C = 2 \pi r \] Using \(r = 63\) and \(\pi = 3.14\): \[ C = 2 \times 3.14 \times 63 = 6.28 \times 63 = 395.64 \] So, the approximate circumference is 395.64.

  2. Circumference of a circle with diameter 20:

    The formula for circumference is also: \[ C = \pi d \] Using \(d = 20\): \[ C = 3.14 \times 20 = 62.8 \] So, the approximate circumference is 62.8.

  3. Diameter from circumference of 574 meters:

    We can use the circumference formula to find diameter: \[ C = \pi d \quad \Rightarrow \quad d = \frac{C}{\pi} \] Using \(C = 574\) and \(\pi = 3.14\): \[ d = \frac{574}{3.14} \approx 183.29 \] Rounded to the nearest tenth, the diameter is 183.3 meters.

  4. Circumference of a circle with radius 38 inches:

    Using the circumference formula: \[ C = 2 \pi r \] Using \(r = 38\): \[ C = 2 \times 3.14 \times 38 = 6.28 \times 38 = 238.64 \] So, the approximate circumference is 238.64 inches.

  5. Area of a circle with radius 75 mm:

    The area \(A\) is calculated using the formula: \[ A = \pi r^2 \] Using \(r = 75\): \[ A = 3.14 \times (75)^2 = 3.14 \times 5625 = 17625 \] So, the approximate area is 17625.0 mm².

To sum up, here are the answers:

  1. 395.64
  2. 62.8
  3. 183.3
  4. 238.64
  5. 17625.0
uhm 3 and 5 are wrong