refresher
Dealing with ONE "outcome" ...
Simple Event
(or single event)
A simple (or single) event is an event with a single outcome (only one "answer").
  Simple Probabilities (with only one outcome (desired result)):
• The probability of rolling a 3 on a die. (1/6)
• The probability of drawing the ace of hearts from a deck of cards. (1/52)
• The probability of tossing a head with a penny.
(1/2)
     defpossible
In a
simple event, the numerator ("number of times it can occur") will be 1.
cointoss

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Dealing with MORE THAN ONE "outcome" ...
Compound Event
A compound event is the combination of two or more simple events (with two or more outcomes).
 
Compound Probabilities (with more than one outcome (desired result) within a trial ):
• The probability of rolling an even number less than 5 on a die.
(2/6)
    
[Even numbers {2,4,6}; less than 5 {1,2,3,4}; both {2,4}]
• The probability of drawing a red ace from a deck of cards.
(2/52)
    
[red card {26 cards}; ace {4 cards}; both {red ace of hearts, red ace of diamonds}]
• The probability of rolling an even number on a die, then tossing a head on a     penny.
 (3/12)
• The probability of drawing a heart, replacing the card, then drawing a spade.
    (169/2704)
• The probability of tossing three pennies and getting at least 2 heads. (4/8)
talking deck
           defpossible
In a compound event, the numerator ("number of times it can occur") will be greater than 1.

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Remember: When dealing with probability (especially compound probability), a tree diagram will give you a visual representation of what is happening.
A tree diagram will show you the solution.
cardsdice


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