This math skill involves understanding and calculating factorials. A factorial, represented by an exclamation point next to a number, is computed by multiplying the number by all positive integers less than itself down to one. This concept is commonly used in probability calculations.
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Meaning and value of a number in factorial form
Test your understanding of meaning of a factorial by practicing it! Work through the below exercises to use it in practice.
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What is the meaning and value of this factorial? When we see a number with the exclamation point beside it, it is called a factorial, and is used a lot in probability.
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Quite simply, 5 factorial means 5 multiplied in sequence by every smaller number, so 5 times 4 times 3 times 2 times 1
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Anything times 1 is just itself, so we can drop that term
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Multiplying it out, we get 120, so 5 factorial, is equal to 120