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Lv 6
? asked in Science & MathematicsMathematics · 1 decade ago

i am perplexed, would like some help?

i have 20 (different) numbers and would like to figure out how many, 9 number combinations i can create (without repeating any), and if you could also help me figure out how to do this would help.

1 Answer

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  • Anonymous
    1 decade ago
    Favorite Answer

    Selections without repetition are called combinations in mathematics. The number of combinations of x objects chosen from n is given the symbol nCx. Good calculators have a button that will do this.

    20C9 = 167960

    Edit. An alternative if you know the factorial notation is n! / [x! * (n - x)! ]

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