http://www.ck12.org Chapter 1. An Introduction to Independent Events - Basic
(b) LetM=Math test
LetS=Science test
P(M or S) = 0. 70 + 0. 60 − 0. 40
P(M or S) = 0. 90
P(M or S) =90%Lesson Summary
Probability and odds are two important terms that must be identified and kept clear in our minds. The fact remains
that probability affects almost every part of our lives. In order to determine probability mathematically, we need to
consider other definitions such as the difference between independent and dependent events, as well as the difference
between a mutually exclusive event and a mutually inclusive event. The calculations involved in probability are
dependent on the distinction between these (no pun intended!). For mutually inclusive events, it is important to
remember the addition rule so that we do not double count in our calculations.
Points to Consider
- Why is the term probability more useful than the term odds?
- Are VENN DIAGRAMS a useful tool for visualizing probability events?
Vocabulary
Dependent Events
Two or more events whose outcomes affect each other. The probability of occurrence of one event depends on
the occurrence of the other.Independent Events
Two or more events whose outcomes do not affect each other.Mutually Exclusive Events
Two outcomes or events are mutually exclusive when they cannot both occur simultaneously.Mutually Inclusive Events
Two outcomes or events are mutually exclusive when they can both occur simultaneously.Outcome
A possible result of one trial of a probability experiment.Probability
The chance that something will happen.