Probability Review

Front

What is the definition of probability?

Back

Probability is a measure of the likelihood that an event will occur, expressed as a number between 0 and 1.

Front

What does a probability of 0 mean?

Back

A probability of 0 means that the event will not occur.

Front

What does a probability of 1 mean?

Back

A probability of 1 means that the event is certain to occur.

Front

How do you calculate the probability of an event?

Back

Probability = (Number of favorable outcomes) / (Total number of possible outcomes).

Front

What is the probability of picking a red marble from a jar containing 2 pink, 6 red, and 4 blue marbles?

Back

Probability = 6/(2+6+4) = 6/12 = 1/2.

Front

What is the probability of picking a red or blue marble from the same jar?

Back

Probability = (Number of red + Number of blue) / (Total number of marbles) = (6+4)/12 = 10/12 = 5/6.

Front

What is a complementary event in probability?

Back

A complementary event is the event that represents all outcomes not in the event. For example, if event A is 'rolling a 3', then the complement is 'not rolling a 3'.

Front

What is the formula for the probability of the union of two events A and B?

Back

P(A or B) = P(A) + P(B) - P(A and B).

Front

What is conditional probability?

Back

Conditional probability is the probability of an event occurring given that another event has already occurred, denoted as P(A|B).

Front

How do you find the conditional probability of event A given event B?

Back

P(A|B) = P(A and B) / P(B), provided P(B) > 0.