Simple Events Worksheets

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See Ch. 9 Answer Appendix.
See Ch. 9 Answer Appendix.
9 -1
Simple Events
Cheesecake
MAIN IDEA
original
raspberry
FOOD
A cheesecake has four slices of each
Find the probability of a
chocolate turtle
type as shown.
simple event.
What fraction of the cheesecake is
1.
New Vocabulary
chocolate? Write in simplest form.
outcome
Suppose your friend gives you the
2.
simple event
first piece of cheesecake without
probability
asking which type you prefer. Are
random
complementary event
your chances of getting original the
same as getting raspberry?
Math Online
• Concepts In Motion
An outcome is any one of the possible results of an action. A simple
• Extra Examples
• Personal Tutor
event is one outcome or a collection of outcomes. For example, getting
• Self-Check Quiz
a piece of chocolate cheesecake is a simple event. The chance of that
event happening is called its probability.
Probability
Key Concept
Words
If all outcomes are equally likely, the probability of a simple
event is a ratio that compares the number of favorable
outcomes to the number of possible outcomes.
___
number of favorable outcomes
Symbols
P(event)
=
number of possible outcomes
Find Probability
1
What is the probability of rolling an even number on a number
cube marked with 1, 2, 3, 4, 5, and 6 on its faces?
even numbers possible
__
P(even number) =
total numbers possible
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3
1
=
or
6
2
_
1
The probability of rolling an even number is
, 0.5, or 50%.
2
Use the number cube above to find each probability. Write as a
fraction in simplest form.
P(odd number)
P(5 or 6)
P(prime number)
a.
b.
c.
460
Chapter 9 Probability