Factorials are symbolized by exclamation points (!).
A factorial is a mathematical operation in which you multiple the given number by all of the positive whole numbers less than it. In other words \(n!=n \times (n-1) \times … \times 2 \times 1\).
“Four factorial” = \(4!=4\times3\times2\times1=24\)
“Six factorial” = \(6!=6\times5\times4\times3\times2\times1)=720\)
When we discuss probability distributions in STAT 200 we will see a formula that involves dividing factorials. For example,
Here is another example,
Also note that 0! = 1
Here is a brief review of factorials as they will be applied in STAT 200: