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Math Invitational for Girls
2020 MIG
22
22
Part of
2020 MIG
Problems
(1)
2020 Individual #22
Source:
5/1/2022
Jane's uncle gives her a "
4
4
4
-balance." The
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4
4
-balance acts like a normal balance scale, but it compares four masses instead of two, tilting towards the weight that is heaviest (if all four are equal, it stays balanced). He then gives her
25
25
25
coins, one of which is a counterfeit heavier than the rest. What is the minimum number of uses of the
4
4
4
-balance needed to ensure she identifies the counterfeit?
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5
<span class='latex-bold'>(A) </span>1\qquad<span class='latex-bold'>(B) </span>2\qquad<span class='latex-bold'>(C) </span>3\qquad<span class='latex-bold'>(D) </span>4\qquad<span class='latex-bold'>(E) </span>5
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5
2020 Individual