What is the area of circle with a diameter of 12 inches?

1 Answer
Feb 14, 2018

The formula for the area of a circle is

#A = pir^2#

Where:

#A# is the Area

#r# is the radius

However, we also know that;

#d = 2r# or #d/2 = r#

So, for this problem the radius is:

#(12"in")/2 = r#

#6"in" = r#

#r = 6"in"#

Substituting this into the formula gives:

#A = pi(6"in")^2#

#A = pi36"in"^2#

#A = 36pi"in"^2#

We can use 3.14 to approximate #pi# giving:

#A = 36 xx 3.14"in"^2#

#A = 113.04"in"^2#