how many ways can 4 letter permutations be formed from the first 5 letters of the alphabet?
how many ways can 4 letter permutations be formed from the first 5 letters of the alphabet?
Answer
Explanation:
Step1: Identify permutation formula
The permutation formula is $P(n,r)=\frac{n!}{(n - r)!}$, where $n$ is the total number of items and $r$ is the number of items to be selected. Here $n = 5$ (the first 5 letters of the alphabet) and $r=4$.
Step2: Calculate factorial values
$n!=5!=5\times4\times3\times2\times1 = 120$, $(n - r)!=(5 - 4)!=1!=1$.
Step3: Substitute into formula
$P(5,4)=\frac{5!}{(5 - 4)!}=\frac{120}{1}=120$.
Answer:
120