General Rules
Given an event, A, what equation gives you the probability that event A will NOT occur?
What is ....
P(A') = 1 - P(A)
or
P(A')+P(A)=1
A coin is tossed 3 times. What is the probability that it lands on heads exactly one time?
What is...
0.375
Events that do not impact each other's probability.
What is...
independent
What is ...
P(rolling three 4s) = P(4)*P(4)*P(4) = P(4)^3
or (1/6)*(1/6)*(1/6)= (1/6)^3
The probability of a female choosing football as their favorite sport.
What is ...
13/100 = .13
Given two independent events, A and B, what is the probability that event A and B occurs.
What is...
P(A and B) = P(A) * P(B)
Armando is a high school baseball player. He gets a hit 70% of the time. That means his average is 0.70. What is the probability that he gets his first successful hit on his third swing?
What is ...
0.3*0.3*0.7= 0.063
two events that cannot occur simultaneously
What is....
mutually exclusive or disjoint
The rule for the probability of pulling a red or queen from a standard deck of cards.
What is...
P(Red or Queen)= P(red)+P(queen) - P(red and queen)
The probability of football not being the favorite sport, given that the student is male.
What is ...
24/48 = .5833
Given two mutually exclusive events, A and B, what is the probability that event A or event B occurs?
What is ...
P(A or B)= P(A) + P(B)
One of two equations used to determine independence between 2 events.
What is...
P(A|B)=P(A)=P(A|not B)
or
P(A and B)=P(A)*P(B)
two events that cannot occur together, but one must happen
What is...
complementary
The rule for finding the probability of a female given that they are an AP stats student.
The probability that the student selected is male given that they prefer baseball.
What is....
13/36 = .361111
Given two events, A and B, what is the probability that event A and B occurs.
What is...
P(A and B) = P(A) * P(B|A)
90% of the people who have a particular disease will have a positive result on a given diagnostic test (90% accuracy). If 5% of a certain population has the disease, what percent of that population would test positive for the disease?
What is ...
14% or 0.14
events that do impact each other's probability
what is ...
dependent
The probability of not drawing a red ace or a club from a standard deck of card
What is ...
1- P(drawing a red ace) - P(drawing a club)Knowing the student is female, the probability that her favorite sport is basketball.
What is ...
16/52 = .3077 = .308