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Frank needs to check the area enclosed by the figure. The figure is made by attaching semi circles to each side of a 48 m x 48 m². Frank says the area is 1313. 28 m². find the area enclosed by the figure. use 3.14 for pie. what error might Frank have made?

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The correct area enclosed by the figure is 9538.56 m², not 1313.28 m² as claimed by Frank. Frank's error likely occurred when subtracting the area of the square from the area of the four semicircles.

Frank needs to determine the area enclosed by a figure created by attaching four semicircles to each side of a square with dimensions 48 m x 48 m.

1. Find the area enclosed by the figure.

2. Identify the error made by Frank, who initially claimed the area was 1313.28 m².

1. Find the area of the 4 semi-circles:

The area of one full circle is given by the formula A = πr², where r is the radius. Since these are semicircles, we need to halve the result.


\( Area_(semicircle) = (1)/(2) \pi ((48)/(2))² \)

Calculate this for one semicircle, and then multiply by 4 for all four.

2. Find the area of the square:

Area_{square} = 48 × 48

3. The area enclosed by the figure:

Add the area of the 4 semicircles to the area of the square.

Area_{enclosed} = Area_{square} + Area_{4 semicircles}

Error made by Frank:

Frank claimed the area was 1313.28 m², but this seems to be incorrect.

Area_{enclosed} = 4 × 1/2 × π × (48/2)² + 48 × 48

Area_{enclosed} = 4 × 1/2 × 3.14 × 24² + 48 × 48

Area_{enclosed} = 4 × 3.14 × 576 + 48 × 48

Area_{enclosed} = 7234.56 + 2304

Area_{enclosed} = 9538.56 m²

Complete question:

Frank needs to check the area enclosed by the figure. The figure is made by attaching semi circles to each side of a 48 m x 48 m². Frank says the area is 1313. 28 m². find the area enclosed by the figure. use 3.14 for pie. what error might Frank have made?

Frank needs to check the area enclosed by the figure. The figure is made by attaching-example-1
User Samir Rahimy
by
3.5k points
6 votes

ANSWER

Area is 5921.28 m^2

Frank made an error by subtracting the area of the square from the area of the 4 semi-circles.

Step-by-step explanation

Given:

Desired outcome:

1. Area enclosed by the figure

2. The error made by Frank.

Find the area of the 4 semi-circles


\begin{gathered} Area\text{ of a semi-circle = }\frac{\pi\text{ r}^2}{2} \\ \text{ = }(3.14*(24)^2)/(2) \\ \text{ = 904.32} \end{gathered}
\begin{gathered} Area\text{ of 4 semi-circles = 4}*904.32 \\ \text{ = 3617.28 m}^2 \end{gathered}

Find the area of the square


\begin{gathered} Area\text{ of a square = l}^2 \\ \text{ = 48}^2 \\ \text{ = 2304 m}^2 \end{gathered}

The area enclosed by the figure

The area enclosed by the figure is determined by adding the area of the 4 semi-circles to the area of the square.


\begin{gathered} Area\text{ enclosed by the figure = Area of the square + area of the 4 semi-circles} \\ \text{ = 2304 + 3617.28} \\ \text{ = 5921.28 m}^2 \end{gathered}

Error made by Frank

Frank made an error by subtracting the area of the square from the area of the 4 semi-circles

i.e:


3617.28\text{ - 2304 = 1313.28 m}^2

Hence, the area enclosed by the figure is 5921.28 m^2 and Frank made an error by subtracting the area of the square from the area of the 4 semi-circles.

Frank needs to check the area enclosed by the figure. The figure is made by attaching-example-1
User Ericca
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2.9k points