Yeh...I didn't use pi in my calculation, but I did use a consistent price. LOL!
http://biglouspizzaonline.com/menu/
You are using the one-topping price ($8.89) for the 10" and the cheese-only price ($51.09) for the 42" pie.
Actually, I'm not sure if you rounded the price up a penny or transposed the penny digits. I assumed the former and used the $56.09 price for the one-topping 42" pie. The ratio of the areas is the same, of course, so your $2.90 is correct for the cheese-only pie and my $3.18 price is correct for one topping.
That the $2.90 estimate is the equivalent of a 44" pie at the one-topping price is a coincidence that led me to err by assuming you used the wrong radius. Sorry 'bout that.
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