2 items are filed under this topic.
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Friends in a class |
2009-09-14 |
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From pran: it is known that among any group of three students in a class two of them are friends. the total number of students is 25. prove that there is a student who has at least 12 friends Answered by Claude Tardif. |
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Divisibility by 2 or 5 or both |
2003-10-30 |
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From Abdu: How many positive integers less than 1,001 are divisible by either 2 or 5 or both? Answered by Penny Nom. |
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