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MAA AMC
AMC 8
2022 AMC 8 -
9
9
Part of
2022 AMC 8 -
Problems
(1)
Temperature of A Boiling Cup (2022 AMC 8 P9)
Source:
1/25/2022
A cup of boiling water (
21
2
∘
F
212^{\circ}\text{F}
21
2
∘
F
) is placed to cool in a room whose temperature remains constant at
6
8
∘
F
68^{\circ}\text{F}
6
8
∘
F
. Suppose the difference between the water temperature and the room temperature is halved every
5
5
5
minutes. What is the water temperature, in degrees Fahrenheit, after
15
15
15
minutes?
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77
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86
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92
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98
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<span class='latex-bold'>(A)</span> ~77\qquad<span class='latex-bold'>(B)</span> ~86\qquad<span class='latex-bold'>(C)</span> ~92\qquad<span class='latex-bold'>(D)</span> ~98\qquad<span class='latex-bold'>(E)</span> ~104\qquad
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86
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92
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98
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104
AMC 8
2022 AMC 8