- Probability { P(A)}is used to make predictions that an
event will happen or not happen.
- P(A)= number of successful
outcomes
-
total number of outcomes
- Simple Probability: When there is one event:
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for a video and sound presentation.
- What is the probability of rolling a 1 on the first throw? There is
one 1 on the dice and 6 different sides.
- P(A)= number of successful outcomes 1 0ne
or 1
- total number of outcomes 6 six sides6
- Example
- What is the probability of selecting one blue marble from a jar that
has 6 red, 6 green, and 3 blue marbles?
- P(A) = number of successful outcomes 3 blue reduce
1 or 20%
-
total number of outcomes 15
total 5
- Compound Probability : has 2 or
more independent events.
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for a video and sound presentation.
- To find the probability, multiply the independent
probabilities together.
- Example
- What is the percent of probability for both A and B spinners not to
land on a 1.
- Spinner A would be 5/6 ( all other possibilities other than a 1)
- Spinner B would be 5/6
- Multiply the 2 together. 5 X 5 = 25
-
6 x 6 = 36
- divide 25 by 36 = .694444 = 69. 4 %
