What is the radius of a circle whose circumference is #16π#?

1 Answer
Nov 24, 2015

Answer:

#8#

Explanation:

The circumference of a circle is equal to #pi#, which is a number #~~3.14#, multiplied by the diameter of the circle.

Therefore, #C=pid#.

We know that the circumference, #C#, is #16pi#, so we can say that:

#16pi=pid#

We can divide both sides by #pi# to see that #16=d#.

We now know that the diameter of the circle is #16#.

We also know that the diameter has twice the length of the radius.

In equation form: #2r=d#

#2r=16#

#color(red)(r=8#

Note that since #2r=d#, the equation #C=2pir# holds and can be used in place of #C=pid#.