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A circular hot spring has a diameter of 96 meters. Over time, the diameter of the spring decreases by 8 meters. By how many square meters does the area of the hot spring decrease? Use 3.14 for pi.

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A circular hot spring has a diameter of 96 meters. Over time, the diameter of the-example-1
User Scalbatty
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1 Answer

23 votes
23 votes

The area decreases by 1155.52 square meters

Explanation:

What we must do is calculate the area before and after making the diameter cut.

The area of a circle is equal to:

a = pi * r ^ 2

now the diameter is equal to:

d = 2 * r

therefore r,

r = d / 2

before the cut would be

r = 96/2

r = 48

replacing in the area formula

a1 = 3.14 * 48 ^ 2

a1 = 7234.56 square meters.

after cutting the diameter decreases by 8, that is, 96 - 8 = 88, calculating the radius would be:

r = 88/2

r = 44

now calculating the new area would be:

a2 = 3.14 * 44 ^ 2

a2 = 6079.04 square meters.

now we calculate the difference

a1 - a2 = 7234.56 - 6079.04

= 1155.52 square meters

means that the area decreases by 1155.52 square meters

User Bryan Gentry
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