This math topic focuses on finding the outer radius of a donut-shaped figure, given its area and inner radius. This is part of introductory geometry, specifically concerning circle areas, sectors, and circular segments (often termed "donuts"). Each question provides a specific inner radius and total area, and the challenge is to determine the donut's outer radius. Options for the outer radius are given as multiple-choice answers, requiring an understanding of how to manipulate the formulas for the area of a circle to solve for the outer radius.

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Area of a Circle Donut From Inner Radius and Area to Outer Radius (Closest Integer) Worksheet

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Area of a Circle Donut From Inner Radius and Area to Outer Radius (Closest Integer)
1
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Find the outer radius of the donut with an area of 188.5 and an inner radius of 2
a
12
b
5
c
2
d
13
e
6
f
8
2
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Find the outer radius of the donut with an area of 75.4 and an inner radius of 1
a
1
b
4
c
7
d
9
e
5
f
10
3
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Find the outer radius of the donut with an area of 34.56 and an inner radius of 5
a
6
b
14
c
11
d
10
e
1
f
5
4
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Find the outer radius of the donut with an area of 50.27 and an inner radius of 3
a
14
b
5
c
13
d
4
e
8
f
1
5
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Find the outer radius of the donut with an area of 172.79 and an inner radius of 3
a
10
b
16
c
1
d
11
e
14
f
8
6
An svg image showing a math problem
Find the outer radius of the donut with an area of 75.4 and an inner radius of 5
a
13
b
14
c
7
d
8
e
3
f
1
7
An svg image showing a math problem
Find the outer radius of the donut with an area of 100.53 and an inner radius of 2
a
13
b
3
c
2
d
6
e
8
f
1
8
An svg image showing a math problem
Find the outer radius of the donut with an area of 47.12 and an inner radius of 1
a
2
b
13
c
11
d
6
e
4
f
1