Can you get to 10 from the numbers 1, 1, 5, 8? You have to use all the numbers, and you have to each number exactly once. You can use - ÷ × and parentheses (). You are not allowed to use exponents, so 10 = 8 1 1^5 is not a valid solution. This problem went viral when Google Japan used it in a commercial for Nexus 7: List of all possible combinations (Google spreadsheet):
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