Small pizza - 10 inches in size - costs $10.

Large pizza - 15 inches in size - costs $20.

Case I - when they buy pizzas alone:

A can buy 1 Small and 1 Large, total square inches = (10)^2 + (15)^2 = 100+225 = 325 inch squared.

B can buy 1 Small and 1 Large, total square inches = (10)^2 + (15)^2 = 100+225 = 325 inch squared.

Total inches = 650.

Case II - when they buy together: they can buy one of the following:

(i) 3 Large - 3(15)^2 = 675 inch squared.

(ii) 2 Large + 2 Small = 2(15)^2 + 2(10)^2 = 450 + 200 = 650 inch squared.

(iii) 1 Large + 4 Small = (15)^2 + 4(10)^2 = 225 + 400 = 625 inch squared.

(i) gives the maximum area, so they would get (675-650) = 25 inch squared more. Ans D.

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