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Problems
Contests
National and Regional Contests
Canada Contests
Gauss
1998 Gauss
21
21
Part of
1998 Gauss
Problems
(1)
Gauss (7) #21
Source:
2/26/2017
Ten points are spaced equally around a circle. How many different chords can be formed by joining any 2 of these points? (A chord is a straight line joining two points on the circumference of a circle.)
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45
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66
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<span class='latex-bold'>(A)</span>\ 9 \qquad <span class='latex-bold'>(B)</span>\ 45 \qquad <span class='latex-bold'>(C)</span>\ 17 \qquad <span class='latex-bold'>(D)</span>\ 66 \qquad <span class='latex-bold'>(E)</span>\ 55
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55
Gauss