1. Unit 4 – Combinatorics and Probability Section 4
Unit 4 – Combinatorics and Probability Section 4.2 – Permutations and Combinations Calculator Required

2. Permutation – The number of ways to ARRANGE ‘n’ items ‘r’ at
a time with no restriction.
Combination – The number of ways to CHOOSE ‘n’ items ‘r’ at
a time with no restriction.

3. A club has 15 members. How many different ways can:
A president, vice-president, and treasurer be selected?
Three officers be selected?

4. A bag contains six white, four red and two blue balls. If four are
drawn, how many ways are there to choose:
3 white and 1 red balls?
2 red and 2 blue balls?
4 red balls?

5. A bag contains six white, four red and two blue balls. If four are
drawn, how many ways are there to choose:
at least three red balls?
three red balls OR four red balls
CALCULATORS AWAY FOR THE DAY
at least one white ball?
one white OR two white OR three white OR four white

6. How many different committees of 3 people can be formed
from a pool of seven people?
In how many ways can a committee consisting of two faculty
members and three students can be formed if six faculty
members and ten students are eligible to serve on the
committee?

7. In a standard deck of cards, how many ways are there to get
three of a kind in a five card hand?
In a standard deck of cards, how many ways are there to get
a flush (5 of the same suit) in a five card hand?
In a standard deck of cards, how many ways are there to get
two pairs in a five card hand?