SOLUTION: The circumference of a circle is 42 meters. What is the approximate radius of the circle?

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Question 333634: The circumference of a circle is 42 meters. What is the approximate radius of the circle?
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
C=2pi%2Ar Start with the circumference of a circle formula.


C%2F%282pi%29=r Divide both sides by 2pi to isolate "r".


r=C%2F%282pi%29 Flip the equation.


r=42%2F%282pi%29 Plug in C=42.


r=42%2F%282%2A3.14159%29 Replace pi with 3.14159 (note: Use more digits of pi to get better accuracy).


r=42%2F%286.28318%29 Multiply 2 and 3.14159 to get 6.28318.


r=6.68451325602641 Divide 42 into 6.28318 to get 6.68451325602641 (this figure is approximate).


r=6.685 Round to the nearest thousandth.


So the radius of a circle which has a circumference of 42 meters is about 6.685 meters.