Use ratio of side lengths to find missing side

The ratio of side lengths for a triangle is exactly 7:11:13. In a second triangle, similar to the first, the shortest side is 9 inches long. To the nearest tenth of an inch, what is the length of the longest side of the triangle?
A.) 14.1
B.) 15
C.) 16.7
D.) 17.3
E.) Cannot be determined from the given information

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If the ratio of the side lengths of the first triangle is 7:11:13, and the second triangle is similar to the first, then a proportion can be created.

The shortest side of the second triangle is 9 inches.

7/13 = 9/x {compared smallest to largest in first triangle and smallest to largest in second triangle, and set them equal, creating the proportion}
7(x) = 13(9) {cross-multiplied}
7x = 117 {multiplied 13 by 9}
x ≈ 16.7 {divided each side by 7 and rounded to the nearest tenth}

the longest side is C.) 16.7 inches

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