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Flashcards in Probability Deck (22)
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1
Q

What is probability ?

A

The chance or likelihood that an event will occur

2
Q

How can you express probability in a formula ?

A

(Desired or winning outcomes )/ possible outcomes

3
Q

What is the highest probability an event can have ?

A

1, 100% , 1/1

4
Q

What is the lowest probability an event can have ?

A

0, 0%, 0/1

5
Q

How do you calculate the probability that an event wont occur ?

A

1 - the probability that it WILL occur

6
Q

Probability of winning + probability of losing =

A

1

7
Q

How do you calculate the amount of numbers in a set if the set includes those two numbers

A

Difference of the two numbers + 1

8
Q

How do you solve an “and” probability?

A

Multiply the probabilities of each event together

9
Q

What is the butterfly effect when it comes to probability ?

A

The probability of subsequent selections will be affected

10
Q

Be careful of problems that imply a sequence of events and ask for the probability of a single event ….

A

Consider the sequence of events that would have to occur for that single event to occur

11
Q

How do you solve or probabilities?

A

Add the probabilities of the individual events involved

12
Q

Probability questions that ask about “more than” , “less than” or “at least” signify what?

A

The question is an OR probability

13
Q

What is the equation for or probabilities that can occur together i.e. pick something white, or a t shirt , and their is a white t shirt that can be selected

A

Can occur together= OR - AND

14
Q

How do you determine the probability that a certain outcome occurs at least once?

A

Subtract the probability that the event never occurs from one

15
Q

When you have probabilities problems where multiple scenarios can lead to a desired outcome what do you do?

A

Add the probabilities of each scenario

16
Q

How do you solve probability questions where various selections must be different?

A

Subtract the probability that the selections are the same from one

1- same

17
Q

If one or more path can lead to a desired outcome what should you do?

A

Add their probabilities

18
Q

What tool can be used for complex desires scenarios?

A

Tree diagrams

19
Q

When do you use tree diagrams for probability problems ?

A

When the problem states a desires outcome or says what it chosen

20
Q

What key words let you know a question is a probability/combinatorics question?

A

Ordered, arranged, scrambled, aligned

21
Q

How do you solve probability/ combinatoric questions?

A

Divide the number of desired arrangements by the total number of possible arrangements

22
Q

How do you approach probability combination problems with “of phrases”?

A

Divide the winning combinations by the total number of possible outcomes

*of phrases should be treated as combinations