



 
Hi Penny, For any positive integer the factorial of that integer is the product of all positive integers less than or equal to the original integer. Thus foe example $3! = 3 \times 2 \times 1 = 6$ and $5! = 5 \times 4 \times 3 \times 2 \times = 120.$ By convention we also say that $0! = 1.$ I hope this helps,  


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