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Weekly Problem 31 - 2012

Weekly Problem 31 - 2012

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Weekly Problem 32 - 2012

Weekly Problem 32 - 2012

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Weekly Problem 34 - 2012

Weekly Problem 34 - 2012

Weekly Problem 38 - 2007

Stage: 3 Challenge Level: Challenge Level:1
Whatever the msising number is, the median and mode will still be 7. For the mean to be 7, the total must be 35. So the missing number is 9.

This problem is taken from the UKMT Mathematical Challenges.

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