What is the radius of a circle with a circumference of 22?

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Answer 1 · 2015-11-10T21:07:37

Approximately #7/2#, exactly #11/pi#

The circumference of a circle is of length #2pi r# where #r# is the radius.

So in our case

#22 = 2 pi r#

Divide both sides by #2 pi# to get:

#r = 22 / (2 pi) = 11/pi#

One well know approximation for #pi# is #22/7#, which gives the approximation:

#r ~~ 11/(22/7) = 7/2#