FORMULAS
Permutation rule formula?
nPr= n!/(n-r)!
What is a combination?
It is a selection of distinct objects without regard to order.
Combination rule definition:
The number of combinations of r objects taken from n objects (order is not important)
If an event E is certain, then the probability of E is …
What rule is it?
1, Probability Rule 3
The manager of a department store chain wishes to make four-digit identification cards for her employees. How many different cards can be made if she uses the digits 1, 2, 3, 4, 5, and 6 and repetitions are permitted?
1296
Combination rule formula?
nCr= n!/(n-r)!r!
Two events are mutually exclusive events…
If they cannot occur at the same time
The number of permutations of n objects taking r objects at a time (order is important) is:
Permutation rule
when two events are ________ , the probability of both occurring is P(A and B) = P(A) x P(B)
independent → Multiplication Rule 1
In 2004, 57.2% of all enrolled college students were female. Choose one enrolled student at random. What is the probability that the student was male?
42.8%
Formula for empirical probability?
P(E)= frequency for the class/total frequencies in the distribution = f/n
It is the set of all possible outcomes of a probability experiment.
Sample space
TRUE OR FALSE? Probability Rule 4: The sum of the probabilities of all the outcomes in the sample space is 1.
true
Addition Rule 1: When two events A and B are mutually exclusive, the probability that A or B will occur is…
P(A or B)= P(A)+ P(B)
A store has 6 TV Graphic magazines and 8 Newstime magazines on the counter. If two customers purchased a magazine, find the probability that one of each magazine was purchased.
48/91
Name of this formula? P(E)= n(E)/ n(S)
classical probability
The complement of an event E is
The set of outcomes in the sample space that are not included in the outcomes of event E.
If an event E cannot occur…
Its probability is 0. → Probability Rule 2
If A and B are not mutually exclusive, then P(A or B)= P(A)+ P(B)- P(A and B) What rule is it?
Addition Rule 2
On New Year’s Eve, the probability of a person driving while intoxicated is 0.32, the probability of a person having a driving accident is 0.09, and the probability of a person having a driving accident while intoxicated is 0.06. What is the probability of a person driving while intoxicated or having a driving accident?
P(intoxicated or accident) = P(intoxicated) + P(accident) - P(intoxicated and accident)= 0.32 + 0.09 - 0.06 = 0.35
Name of this formula? P(B|A)= P(A and B)/P(A)
conditional probability
What is a probability experiment?
It is a chance process that leads to well-defined results called outcomes.
Fundamental counting rule definition:
The number of ways a sequence of n events can occur if the first event can occur in k1 ways, the second event can occur in k2 ways, etc.
Describe Multiplication Rule 2 with the formula
When two events are dependent, the probability of both occurring is P(A and B)= P(A) x P(B|A).
The probability that Sam parks in a no-parking zone and gets a parking ticket is 0.06, and the probability that Sam cannot find a legal parking space and has to park in the noparking zone is 0.20. On Tuesday, Sam arrives at school and has to park in a no-parking zone. Find the probability that he will get a parking ticket.
0.30