Answer:
the 2nd one
Step-by-step explanation:
75 42
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100 x
75 x= 4200
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75 75
x = 56
Step-by-step explanation:

Area od pizza, A = Pi*Diameter^2/4
A1 = Pi*8^2/4 = 50.27 in^2
A2 = Pi*10^2/4 = 78.54 in^2
A3 = Pi*12^2/4 = 113.10 in^2
Cost (C) per sq. in;
C1 = 50.27/9 = $5.59
C2 = 78.54/12 = $6.55
C3 = 113.10/18 = $6.28
The best buy is the first pizza with 8 in diameter as it costs the least per sq. inch.