Question
Suppose we want to choose 4 letters, without replacement, from 17 distinct letters.
(If necessary, consult a list of formulas.)
(b) If the order of the choices is not relevant, how many ways can this be done?
(If necessary, consult a list of formulas.)
Ask by Patel Marsh. in the United States
Mar 15,2025
Upstudy AI Solution
Tutor-Verified Answer
Answer
(a) There are 57,120 ways to choose 4 letters from 17 distinct letters when the order matters.
(b) There are 2,380 ways to choose 4 letters from 17 distinct letters when the order does not matter.
Solution

Sign in to Unlock Answers for Free!
A Learning Platform Trusted by Millions of Real Students and Teachers.

Answered by UpStudy AI and reviewed by a Professional Tutor
Like
Bonus Knowledge
To solve part (a), where order matters, we use permutations. The number of ways to choose 4 letters from 17 distinct letters is given by the formula for permutations:
Here,
is 17 and
is 4. Thus,
So, there are 57,120 ways to choose 4 letters if the order of the choices is relevant.
For part (b), where order does not matter, we use combinations. The number of ways to choose 4 letters from 17 is given by the formula for combinations:
Thus,
Therefore, there are 2,380 ways to choose 4 letters without caring about the order.