Posted by Anonymous on .
If a circle's circumference is 15 inches, what is its radius?

Algebra 1 I do not understand 
Ms. Sue,
C = pi * d
15 = 3.14 * d
15/3.14 = d
4.77707 = d
4.77707 / 2 = r
2.388535 = r 
Algebra 1 I do not understand 
Anonymous,
I still don't understand this.

Algebra 1 I do not understand 
Anonymous,
Can you explain the steps in solving this formula?

Algebra 1 I do not understand 
Ms. Sue,
Please copy and paste the line you don't understand.

Algebra 1 I do not understand 
Anonymous,
C = pi * d
15 = 3.14 * d
15/3.14 = d
4.77707 = d
4.77707 / 2 = r
I apologize, but I do not understand any of them. 
Algebra 1 I do not understand 
Ms. Sue,
Circumference = pi * diameter
Then I substituted real numbers for the letters. 
Algebra 1 I do not understand 
Anonymous,
How did you know which numbers to use?

Algebra 1 I do not understand 
Ms. Sue,
Please memorize pi = 3.154
Your problem stated that the circumference is 15.