2019 AMC 12A Problems/Problem 1

Problem

The area of a pizza with radius $4$ is $N$ percent larger than the area of a pizza with radius $3$ inches. What is the integer closest to $N$ ?

$\textbf{(A) } 25 \qquad\textbf{(B) } 33 \qquad\textbf{(C) } 44\qquad\textbf{(D) } 66 \qquad\textbf{(E) } 78$

Solution

The area of the larger pizza is $16\pi$ , while the area of the smaller pizza is $9\pi$ . Therefore, the larger pizza is $\frac{7\pi}{9\pi} \cdot 100\%$ bigger than the smaller pizza. $\frac{7\pi}{9\pi} \cdot 100\% = 77.777....$ , which is closest to $\boxed{\textbf{(E) }78}$ .

Video Solution 1

https://youtu.be/SbUEin-OE-k

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2019 AMC 12A (Problems • Answer Key • Resources)
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All AMC 12 Problems and Solutions

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2019 AMC 12A Problems/Problem 1

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Problem

Solution

Video Solution 1

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