Probability Study Guide

Shannon has a bag of jelly beans. She removed one jelly bean, recording the color, and then replaced it. She repeated the process several times and record her results in the table. What is the experimental probability of her selecting a red jelly bean?

• 11/33

• 1/3

• 1/4

• 18/26

There are 23 marbles, each a different color in a bag. One of them is pink. What is the probability of reaching in to the bag, without looking, and selecting a pink marble?

• 1/22
• 1/23
• 23/1

There are 15 girls and 13 boys in 6th period. If Coach Mullins randomly selects a member of 6th period, what is the probability that she will select a boy?

• 13/15

• 1/2

• 15/40

• 13/28

P(not A) = 
*Remember to simplify.*

• 6/8
• 3/4
• 2/8
• 1/4

The cafeteria has 2 choices of salads, 3 choices of entrees, and 2 choices of beverages. How many meal combinations are available and why?

• 7 because 2 + 3 + 2
• 12 because 2(3)(2)

Which of the following situations is represented by this tree diagram?

• 3 shirt options, 6 pants options, and 12 shoe options
• 3 shirt options, 2 pants options, and 2 shoe options
• 2 shirt options, 3 pants options, and 1 shoe option

How many total outfit options are represented?

• 12
• 22
• 3

The chart below represents the number of marbles in a jar.
P(green) = 

• 5/19
• 10/28
• 5/14

You spin this spinner 3 times.
Find the probability of these 3 events.
P(red, odd, 3)

• 1/216
• 1/72
• 1/36
• 1/12

A farm has 5 brown cows and 10 white cows. A fence is open and two cows escape. What is the probability that it will be a brown cow, then a white cow?

• 1/9
• 2/9
• 5/21
• 10/21