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National and Regional Contests
Turkey Contests
National Olympiad First Round
2002 National Olympiad First Round
7
7
Part of
2002 National Olympiad First Round
Problems
(1)
P07 [Combinatorics] - Turkish NMO 1st Round - 2002
Source:
8/7/2014
What is the least number of weighings needed to determine the sum of weights of
13
13
13
watermelons such that exactly two watermelons should be weighed in each weigh?
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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>\ 9 \qquad<span class='latex-bold'>d)</span>\ 10 \qquad<span class='latex-bold'>e)</span>\ 11
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