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That's your answer. These are what are mathematically called "combinations". You can use a formula involving factorials to determine the number of combinations. In this case, we say this is "10 Choose 3" and write it as _{10}C_{3}. That means from a set of ten (digits in The formula for _{n}C_{m} is
So in your question, we have
For more information on Combinations and their close cousins Permutations (where order matters), look up these words in our Quick Search. Cheers,  


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