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MAA AMC
AMC 12/AHSME
2019 AMC 12/AHSME
11
Edge Pairs
Edge Pairs
Source: 2019 AMC 12 B # 11
February 14, 2019
AMC
AMC 12
AMC 12 B
geometry
3D geometry
Problem Statement
How many unordered pairs of edges of a given cube determine a plane?
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21
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28
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36
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42
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66
<span class='latex-bold'>(A) </span> 21 \qquad<span class='latex-bold'>(B) </span> 28 \qquad<span class='latex-bold'>(C) </span> 36 \qquad<span class='latex-bold'>(D) </span> 42 \qquad<span class='latex-bold'>(E) </span> 66
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28
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36
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42
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66
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