1. To make a ratio… Chance of the event total number
Lesson 6.6
Concept: How to find the probability of an event
Guidelines: Probability can be expressed as a ratio or a decimal.
To make a ratio… Chance of the event
total number
To change the ratio to a decimal…divide!
Bottom number top number

2. Practice: Find the probability. Express it as a ratio and a decimal.1 2
What is the chance of the spinner landing on the 3? 6 3
1 chance of landing on a “3” 5 4
6 total number of places
1. Create a ratio.
2. Divide to make a decimal.
0. 16
6 ) 1
.00
- 6 40

3. Find an experimental probability…
About how many times can you expect the pointer to land on “3” in the next 50 spins?
Use two ratios and cross products to predict
1 = x