Question

A window is being replaced with tinted glass. The plan at the right shows the design of the window. Each unit length represents 1 foot. The glass costs $28 per square foot. How much will it cost to replace the glass?

Answer 1

$911.68

Explanation:

First separate the window into simpler figures - rectangle and circle. Find the area of the rectangle using A = bh. The area of the rectangle is 20 sq. ft. Find the area of the circle using A = pi*r*r. The area of the circle is 12.56 sq. ft. Sum up the areas together. The area of the window is 32.56 sq. ft. To find the cost to replace the glass multiply 32.56 by $28 totaling $911.68.

Answer 2

The answer is $911.68.

After a little research on the internet, I found the design of the window.
First, you need to find the area of the window which is a composite figure made up of a rectangle and a circle. So, the total area (A) is the sum of the area of the rectangle (A1) and the area of the circle (A2).

Area of the rectangle with length l and width w is:
A = l * w
According to the image, l = 5 ft and w = 4 ft.
A1 = 5 * 4 = 20 ft²

Area of the circle with radius r is:
A = r²π
According to the image, r = 2 ft.
A2 = 2² * 3.14 = 12.56 ft²

The area of the window is:
A = A1 + A = 20 ft² + 12.56 ft² = 32.56 ft²

The glass costs $28 per square foot, so to replace the glass will cost:
32.56 ft² * $28/ft² = $911.68