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Problems
Contests
National and Regional Contests
Turkey Contests
National Olympiad First Round
1999 National Olympiad First Round
7
7
Part of
1999 National Olympiad First Round
Problems
(1)
Probability
Source: 0
4/21/2009
Six cards with numbers 1, 1, 3, 4, 4, 5 are given. We are drawing 3 cards from 6 given cards one by one and are forming a three-digit number with the numbers over the cards drawn according to the drawing order. Find the probability that this three-digit number is a multiple of 3. (The card drawn is not put back)
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1
5
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3
7
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None
<span class='latex-bold'>(A)</span>\ \frac {1}{5} \qquad<span class='latex-bold'>(B)</span>\ \frac {2}{5} \qquad<span class='latex-bold'>(C)</span>\ \frac {3}{7} \qquad<span class='latex-bold'>(D)</span>\ \frac {1}{2} \qquad<span class='latex-bold'>(E)</span>\ \text{None}
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7
3
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None
probability