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Nines and Tens

Explain why it is that when you throw two dice you are more likely to get a score of 9 than of 10. What about the case of 3 dice? Is a score of 9 more likely then a score of 10 with 3 dice?

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Master Minding

Your partner chooses two beads and places them side by side behind a screen. What is the minimum number of guesses you would need to be sure of guessing the two beads and their positions?

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Odds and Evens

Is this a fair game? How many ways are there of creating a fair game by adding odd and even numbers?

At Least One...

Stage: 3 Challenge Level: Challenge Level:1

If there isn't at least one head, what must be true about every flip of the coin?