Question

Many television screens are rectangles that are measured by the length of their diagonals. The ratio of the horizontal length to the height in a standard television screen is $4 : 3.$ The horizontal length of a $27$ -inch television screen is closest, in inches, to which of the following?

$20$

$20.5$

$21$

$21.5$

$22$

Answer: D

Concepts:Pythagorean Triple ratio and proportion

Difficulty rating: 1050

Solution:

A rectangle with side ratio $4 : 3$ has height, length, and diagonal in ratio $3 : 4 : 5.$ With diagonal $27,$ the horizontal length is $\frac{4}{5}(27) = 21.6,$ which is closest to $21.5.$

Thus, the correct answer is D.

2003 AMC 12B Problem 5

Answer: D

Difficulty rating: 1050

Solution:

Problem 5 in Other Years