Question 907822
I didn't' find the price per square inch.
I found the ratio of one pizza to the other in size and in price.


a=pi*r^2
a=pi*5^2=25*pi 
The area of the smaller pizza is 25*pi
a=pi*7.5^2=56*pi
The area of the larger  pizza is 56*pi
We don't need to work out the exact size  because pi will cancel out pi
 (56pi) /(25 pi)= 56 to 25
56/25=2.24
The larger pizza is 2.24 times the size of the smaller
The ratio of the prices is almost 2 to 1

19.99/10=1.999
You are paying less than  2 to 1 but getting 2.24 to 1.

You get more pizza for your dollar if you buy the large.

The other tutor tried to give you the cost per  square inch but put the same price for both