What are the dimensions of the lid with an area of 392 square centimeters and a width to length ratio of 1:8?

Question image

Understand the Problem

The question is asking for the dimensions of a rectangular lid based on its area and width-to-length ratio. We have the area of 392 square centimeters and the ratio of width to length is 1:8. We need to calculate the width and length that fit these criteria.

Answer

$7 \text{ cm}$ by $56 \text{ cm}$
Answer for screen readers

The dimensions of the lid are $7 \text{ cm}$ by $56 \text{ cm}$.

Steps to Solve

  1. Define the variables

Let the width of the lid be $w$ and the length be $l$. According to the ratio given, we can express the length in terms of the width: $$ l = 8w $$

  1. Set up the area equation

We know the area of the rectangle is given by the formula: $$ \text{Area} = w \times l $$

Substituting the expression for $l$, we get: $$ 392 = w \times (8w) $$

  1. Rearrange the equation

This simplifies to: $$ 392 = 8w^2 $$

Dividing both sides by 8 gives: $$ w^2 = \frac{392}{8} $$ $$ w^2 = 49 $$

  1. Solve for width

Taking the square root of both sides: $$ w = \sqrt{49} $$ $$ w = 7 \text{ cm} $$

  1. Calculate the length

Now that we have the width, we can find the length using the equation for $l$: $$ l = 8w = 8 \times 7 = 56 \text{ cm} $$

The dimensions of the lid are $7 \text{ cm}$ by $56 \text{ cm}$.

More Information

The problem involves using the properties of ratios and the area of rectangles to find the dimensions based on a given area and ratio. The width to length ratio of 1:8 means that for every 1 cm of width, there are 8 cm of length.

Tips

  • Mistaking the ratio (1:8) as width being larger than length, when it is the other way around.
  • Forgetting to square root the area when rearranging the equation.

AI-generated content may contain errors. Please verify critical information

Thank you for voting!
Use Quizgecko on...
Browser
Browser