Question

Suppose a​ 10-in. circular pizza costs​ $4.00. To find the​ price, x, of a​ 14-in. circular​ pizza, is it correct to set up the proportion Start Fraction x Over 4 End Fraction equals Start Fraction 14 Over 10 End Fraction ​
A. No, it is not correct. The ratio of the prices is equal to the ratio of the areas and not to the ratio of the diameters
B. No, it is not correct. The ratio of the prices is equal to the ratio of the radii and not to the ratio of the diameters.
C. Yes, it is correct. The ratio of the prices is equal to the ratio of the diameters.
D. 10 No, it is not correct. The ratio of the prices is equal to the ratio of the diameters, but the proportion should be-= X 14
E. Yes, it is correct. The ratio of the prices is equal to the ratio of the areas.

Answer 1

$\bf \begin{array}{ccll} \stackrel{diameter}{in}&\ \\ \cline{1-2} 10&4\\ 14&x \end{array}\implies \cfrac{10}{14}=\cfrac{4}{x}\implies \cfrac{x}{4}=\cfrac{14}{10}\qquad \textit{\huge \checkmark}$