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What are the width and height of a 72-inch diameter television with an aspect ratio of 5:3? (Note: Width is the longer side in the aspect ratio.)

A. Width: 61.5 in, Height: 36.9 in
B. Width: 75.2 in, Height: 84.3 in
C. Width: 36.9 in, Height: 61.5 in
D. Width: 84.3 in, Height: 75.2 in

Answer :

To determine the width and height of a 72-inch diameter television with an aspect ratio of 5:3, we need to consider the relationship between the diameter and the dimensions based on the aspect ratio.

### Steps to solve the problem:

1. Understanding the Aspect Ratio:
- An aspect ratio of 5:3 means that for every 5 units of width, there are 3 units of height.
- Let's denote the width as 5x and the height as 3x, where x is a scaling factor.

2. Relationship with the Diameter:
- Typically, the diameter of the television is the diagonal of the rectangular screen.
- Using the Pythagorean theorem, we can relate the width, height, and diagonal (diameter):
[tex]\( \text{Diagonal} = \sqrt{(\text{Width})^2 + (\text{Height})^2} \)[/tex].

3. Setting Up the Equation:
- Replace the width and height with their expressions in terms of x:
[tex]\( \text{Diagonal} = \sqrt{(5x)^2 + (3x)^2} \)[/tex].
- Plug in the given diagonal (72 inches):
[tex]\( 72 = \sqrt{25x^2 + 9x^2} \)[/tex].
- Simplify the expression under the square root:
[tex]\( 72 = \sqrt{34x^2} \)[/tex].

4. Solving for x:
- Square both sides to eliminate the square root:
[tex]\( 5184 = 34x^2 \)[/tex].
- Divide by 34:
[tex]\( x^2 = \frac{5184}{34} \)[/tex].
- Solve for x by taking the square root:
[tex]\( x = \sqrt{\frac{5184}{34}} \)[/tex].

5. Calculating Width and Height:
- Width: [tex]\( \text{Width} = 5x \)[/tex].
- Height: [tex]\( \text{Height} = 3x \)[/tex].

After calculating, you will find the dimensions are approximately:
- Width: 61.74 inches (closely matching 61.5 inches)
- Height: 37.04 inches (closely matching 36.9 inches)

Given the choices, the correct dimensions that approximate our calculated result are:
- Width: 61.5 inches
- Height: 36.9 inches

Therefore, the correct answer from the choices is:
- Width 61.5 inches and height 36.9 inches.

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