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Math

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How many combinations are there when you can buy four books from a choice of 6 books>

  • Math -

    Combinations = n!/r!(n-r)!

    where n is the number of things to choose from, and you choose r of them
    (No repetition, order doesn't matter)

    5 factorial = 5! = 5 * 4 * 3 * 2 * 1 = 120

    I'll let you do the calculations.

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