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National and Regional Contests
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MAA AMC
AMC 8
2017 AMC 8
24
24
Part of
2017 AMC 8
Problems
(1)
Grandma's Phonecalls
Source: AMC 8 2017 #24
11/22/2017
Mrs. Sanders has three grandchildren, who call her regularly. One calls her every three days, one calls her every four days, and one calls her every five days. All three called her on December 31, 2016. On how many days during the next year did she not receive a phone call from any of her grandchildren?
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78
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144
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<span class='latex-bold'>(A) </span>78\qquad<span class='latex-bold'>(B) </span>80\qquad<span class='latex-bold'>(C) </span>144\qquad<span class='latex-bold'>(D) </span>146\qquad<span class='latex-bold'>(E) </span>152
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152
AMC 8