SOLUTION: Find the area of a circle. Use 3.14 or 22/7 Diameter = 7ft Answer = ? PLEASE HELP!!!!!!

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Question 254296: Find the area of a circle. Use 3.14 or 22/7
Diameter = 7ft
Answer = ?
PLEASE HELP!!!!!!
Found 2 solutions by drk, richwmiller:
Answer by drk(1908) About Me  (Show Source):
You can put this solution on YOUR website!
The area of a circle has formula:
A+=+pi%2Ar%5E2
However if we are given the diameter, we must find radius by dividing by 2.
D = 7 ft
r = 3.5 ft.
22/7 makes more sense here.
A+=+%2822%2F7%29%2A%287%2F2%29%5E2
A+=+%2822%2F7%29%2A%287%2F2%29%2A%287%2F2%29%7D%7D%0D%0A%7B%7B%7BA+=+%2811%29%2A%287%2F2%29
A+=+%2877%2F2%29
or 38.5 square feet.

Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
I will set it up for you.
d=2r
7=2r
7/2=r
3.5=r
A=pi*r^2
A=22/7*(7/2)^2
A=(22/7)*(7*7/(2*2)
A=(22*7*7)/(7*2*2)
I think you can see some cancelling to do
At least 2/2 and 7/7 which is why I chose 22/7 rather than 3.14 for pi and left the radius as 7/2