There are ways for the teacher to decide which student she will teach during each lesson time if she must teach each student exactly 3 times. Here, "!" represents the factorial.
A number's factorial is the result of multiplying the integer by each natural number below it. Factorial can be symbolized by the letter "!". Thus, n factorial is denoted by n! and is the result of the first n natural numbers.
A whole number's "n" factororial is the sum of that number and each whole number up to one.
When a question asks you to determine how many different ways you can arrange or order a given number of items, you use a factorial.
Learn more about factorials here:
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