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NMC 2002 Problem 4

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Eva, Per and Anna play with their pocket calculators. They choose different integers and check, whether or not they are divisible by 11. They only look at nine-digit numbers consisting of all the digits 1, 2, .., 9. Anna claims that the probability of such a number to be a multiple of 11 is exactly 1/11. Eva has a different opinion: she thinks the probability is less than 1/111 / 11. Per thinks the probability is more than 1/111 / 11. Who is correct?

Dataset text NuminaMath olympiads. Quoted with source.

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\frac{11}{126}<\frac{1}{11}

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