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Contests
National and Regional Contests
USA Contests
MAA AMC
AMC 8
2004 AMC 8
12
12
Part of
2004 AMC 8
Problems
(1)
AMC 8 2004 Problem 12
Source:
11/28/2010
Niki usually leaves her cell phone on. If her cell phone is on but she is not actually using it, the battery will last for
24
24
24
hours. If she is using it constantly, the battery will last for only
3
3
3
hours. Since the last recharge, her phone has been on
9
9
9
hours, and during that time she has used it for
60
60
60
minutes. If she doesn't talk any more but leaves the phone on, how many more hours will the battery last?
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7
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8
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11
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14
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<span class='latex-bold'>(A)</span>\ 7\qquad <span class='latex-bold'>(B)</span>\ 8\qquad <span class='latex-bold'>(C)</span>\ 11\qquad <span class='latex-bold'>(D)</span>\ 14\qquad <span class='latex-bold'>(E)</span>\ 15
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7
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8
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11
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14
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15