Probability & its Complement

Front

What is Probability?

Back

Probability is a measure of how likely an event is to occur, expressed as a number between 0 and 1, where 0 means the event cannot happen and 1 means the event is certain.

Front

What is the formula for calculating Probability?

Back

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

Front

What is an even number?

Back

An even number is an integer that is exactly divisible by 2.

Front

How many even numbers are there on a regular die?

Back

There are 3 even numbers on a regular die: 2, 4, and 6.

Front

What is the probability of rolling an even number on a regular die?

Back

P = 3/6 = 1/2.

Front

What is a complement in probability?

Back

The complement of an event is the probability that the event does not occur.

Front

If the probability of an event A is P(A) = 1/4, what is the probability of its complement?

Back

P(A') = 1 - P(A) = 1 - 1/4 = 3/4.

Front

How many total outcomes are there when rolling a regular die?

Back

There are 6 total outcomes when rolling a regular die: 1, 2, 3, 4, 5, and 6.

Front

What is the probability of rolling a 1 on a regular die?

Back

P = 1/6.

Front

What is the probability of NOT rolling a 1 on a regular die?

Back

P' = 1 - P(rolling a 1) = 1 - 1/6 = 5/6.