Consider the following counting problem. How many different sequences of 3 letters can be formed using the letters a, b, c, d, e if repetition is allowed?
To solve this problem which of the following rules would you use?
A)The basic counting rule only
B)The combinations rule only
C)Both the permutations rule and the basic counting rule
D)The permutations rule only

Question

Consider the following counting problem. How many different sequences of 3 letters can be formed using the letters a, b, c, d, e if repetition is allowed?
To solve this problem which of the following rules would you use? 
A)The basic counting rule only
B)The combinations rule only
C)Both the permutations rule and the basic counting rule
D)The permutations rule only

Quizplus · Accepted Answer

Since repetition is allowed and the order of the letters matters, the basic counting rule is sufficient. For each of the 3 positions in the sequence, there are 5 choices (a, b, c, d, e), leading to 5^3 different sequences.

Consider the Following Counting Problem