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A rectangle topped by a semicircle. the rectangle has length of 4 meters and width of 3 meters. the circle has diameter 3 meters. a norman window is rectangular on three sides with a semi-circular top. you decide to install a norman window in your family room with the dimensions indicated in the diagram. what is its perimeter? a. 15.71 feet c. 18.45 feet b. 14.23 feet d. 14 feet

1 Answer

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The perimeter of the Norman window, which consists of a rectangle and a semicircle is approximately 18.71 meters.

Let's calculate the perimeter of the Norman window, which consists of a rectangle and a semicircle.

The rectangle has a length of 4 meters and a width of 3 meters.

The semicircle has a diameter of 3 meters, which means its radius is 3/2 meters.

Now, let's calculate the perimeter:

Perimeter of the Rectangle:


\begin{aligned}& P_{\text {rectangle }}=2(\text { length }+ \text { width }) \\& P_{\text {rectangle }}=2(4+3) \\& P_{\text {rectangle }}=2 * 7 \\& P_{\text {rectangle }}=14 \text { meters }\end{aligned}

Circumference of the Semicircle:


\begin{aligned}& C_{\text {semicircle }}=\pi * \text { radius } \\& C_{\text {semicircle }}=\pi * (3)/(2) \\& C_{\text {semicircle }}=(3 \pi)/(2) \text { meters }\end{aligned}

Perimeter of the Norman Window:


\begin{aligned}& P_{\text {total }}=P_{\text {rectangle }}+C_{\text {semicircle }} \\& P_{\text {total }}=14+(3 \pi)/(2)\end{aligned}

Now, let's calculate the approximate numerical value:


\begin{aligned}& P_{\text {total }} \approx 14+(3 * 3.14)/(2) \\& P_{\text {total }} \approx 14+(9.42)/(2) \\& P_{\text {total }} \approx 14+4.71 \\& P_{\text {total }} \approx 18.71 \text { meters }\end{aligned}

So, the closest option is (c) 18.45 feet. The correct answer is (c) 18.45 feet.

Question:

A rectangle topped by a semicircle. the rectangle has length of 4 meters and width of 3 meters. the circle has diameter 3 meters. a Norman window is rectangular on three sides with a semi-circular top. you decide to install a Norman window in your family room with the dimensions indicated in the diagram. what is its perimeter?

a. 15.71 feet

b. 14.23 feet

c. 18.45 feet

d. 14 feet

User Douglas Held
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