Randomness
This is the term for observable occurrences, like coin flips or dice rolls.
What is a phenomenon?
The complete set of all possible outcomes is called this.
What is a sample space?
An event where all outcomes are equally likely, such as a coin flip, has this probability of heads.
What is 1/2?
Probabilities must always be between these two numbers.
What are 0 and 1?
When flipping a fair coin twice, what is the probability of getting two heads?
What is 1/4 or 0.25?
In the short run, outcomes are unpredictable, but in the long run, this principle explains why probabilities settle toward expected values.
What is the law of large numbers?
Tossing two coins produces this many total outcomes.
What is 4?
An event that contains all outcomes not in event A is called this.
What is the complement of A?
For disjoint events A and B, this is the formula for their union.
P(A or B) = P(A) + P(B)?
The probability of randomly guessing one correct answer on a 5-option multiple choice question.
What is 1/5 (or 0.20)?
The proportion of times an outcome occurs over many trials is called this.
What is relative frequency?
An ordered arrangement of objects, such as the letters in "MATH," is called this.
What is a permutation?
Two events that cannot happen at the same time are called this.
What are disjoint events?
For independent events A and B, this is the formula for their intersection.
What is P(A) × P(B)?
The probability of correctly guessing all 3 answers on such a quiz is this decimal.
What is 0.008?
The probability of rolling a 6 on a fair die in the long run is this fraction.
What is 1/6?
Choosing 3 students from a class of 10 is an example of this.
What is a combination?
The probability of the sum of two dice being 7 is this fraction.
What is 1/6?
If a family has two children, the probability of at least one being a girl is this.
What is 3/4?
The probability of passing the quiz by guessing (at least 2 correct) is about this percent.
What is 10%?
When trials are independent, this rule tells us long-run averages will eventually match theoretical probabilities.
What is the law of averages (law of large numbers)?
The number of outcomes for a three-question quiz (correct/incorrect) is this.
What is 8?
This term describes outcomes that are in both event A and event B.
What is the intersection?
For any two events A and B, the general addition rule states: P(A or B) = P(A) + P(B) – _____.
What is P(A and B)?
If the probability of a first question correct is 0.63 and second is 0.69, but joint probability is 0.58, then the events are not this.
What is independent?