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3 years ago

12

how many meters is the circumference of a circle with a radius of 20 cm?

2 answers:

Ira Lisetskai [31]3 years ago

5 0

Circumference of a circle can be found using formula 2 * pi * radius

20 cm is 0.2 meters

2 * pi * 0.2
0.4 * pi ≈ 1.26

The circumference is approximately 1.26 meters.

Harman [31]3 years ago

4 0

First find the circumference of the circle.
Circumference: $2 \pi r$

Plug in 20 for the radius (r).
$2 \pi20$ = 125.66

The circumference of the circle is 125.66 cm.
Now to find this in meters... there are 100 centimeters in 1 meter.

Divide 125.66 by 100 to find how many meters this is.
125.66 ÷ 100 = 1.26

The circle's circumference is 1.26 meters.

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Rounding up:

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