Probability and Counting Principles

There are 10 counters in a bag, 3 red and 7 blue.

I take one counter, then another without replacement.

Find the probability of the value marked y

• ⁷/₁₀

• ³/₁₀

• ⁶/₉

• ²/₉

The tree diagram shows the outcomes of rolling a die and flipping a coin.  
What is the probability of rolling an even number and flipping a head?

• ³/₁₂

• ¹/₂

• ⁴/₁₂

• ⁰/₁₂

The tree diagram shows the outcomes of rolling a die and flipping a coin.  
How many total outcomes are there?  

• 6

• 12

• 24

• 36

Two dice are rolled and it is recorded whether the result on each is odd or even. What is the probability both are odd?

• 1/4

• 1/2

• 2/4

• 3/4

For breakfast, you can choose to eat cereal or a bagel and to drink coffee, OJ, tea, or water. What is the sample space of this situation?

• 2, because there are 2 things to choose from to eat.

• 4, because there are 4 things to choose from to drink

• 10, because I see 10 different words on the tree diagram

• 8, because there are 8 different outcomes (cereal, coffee) (cereal, OJ) (cereal, tea) (cereal, water) (bagel, coffee) (bagel, OJ) (bagel, tea) (bagel, water)

What is the probability of randomly picking a lunch with pizza, soda, and ice cream?

• 1/18

• 3/18 or 1/6

• 13/18

• 1/3

Q1. How many legs does a spider have?

• 1) 6

• A) 12

• 2) 2

• 3) 10

What is the sample space when you roll a die and then flip a coin?

• 1H, 2H, 3H, 4H, 5H, 6H, 1T, 2T, 3T, 4T, 5T, 6T

• 2

• 1,2,3,4,5,6,H,T

What is the probability of spinning an even number? 

• equally likely

• very likely 

• certain

• impossible 

What is the probability of selecting a cherry piece of candy?

• 3 out of 10

• 3 out of 3

• 3 out of 9

• 4 out of 10