Question

Find the circumference of the circle. Round your answer to the nearest hundredth. Use 3.14 or 227 for π.

There's a picture of a circle with the radius of 21 cm

Picture of the circle:

Answer 1

The circumference of a circle with a radius of 21 cm is calculated using the formula C = 2πr, and with π approximated as 3.14, the circumference is 131.88 cm rounded to the nearest hundredth.

To find the circumference of a circle with a radius of 21 cm, we use the formula C = 2πr. Substituting the given radius and using π = 3.14, we calculate:

C = 2 × 3.14 × 21 cm = 131.88 cm.

So, rounding to the nearest hundredth, the circumference of the circle is 131.88 cm.

Answer 2

65.94cm

Explanation:

The two equivalent equations to find the circumference of a circle are:

Circumference = 2 * pi * radius

Circumference = pi * diameter

Since the diameter of the circle is given, in order to find circumference, plug in 21cm into the 2nd equation:

Circumference = pi * diameter = pi * 21 cm = 3.14 * 21 = 65.94 cm