SOLUTION: A pizza sells a 9 in diameter pizza for $8.00. What is a fiar price for a 13" diameter pizza?

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Question 105859: A pizza sells a 9 in diameter pizza for $8.00. What is a fiar price for a 13" diameter pizza?
Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
A=pi*r^2 r=4.5
pi*4.5^2= 20.25*pi
.
pi*6.5^2= 42.25*pi
.
now we set up a proportion to see what the fai price will be. The pi's cancel out, so we wont put them in.
.
42.25%2F20.25=x%2F8
42.25%2A8%2F20.25=x
x=$16.69 Fair price
Ed