Probability of an Event

Front

What is probability?

Back

Probability is a measure of how likely an event is to occur, expressed as a number between 0 (impossible) and 1 (certain).

Front

What does it mean if an event is 'certain'?

Back

An event is 'certain' if it will definitely happen. For example, the sun will rise tomorrow.

Front

What does it mean if an event is 'impossible'?

Back

An event is 'impossible' if it cannot happen at all. For example, rolling a 7 on a standard 6-sided die.

Front

What does 'unlikely' mean in probability?

Back

'Unlikely' means that an event has a low chance of occurring, but it is still possible.

Front

What does 'likely' mean in probability?

Back

'Likely' means that an event has a high chance of occurring.

Front

What is an example of an 'even chance' event?

Back

An 'even chance' event is one that has a 50% probability of occurring, like flipping a coin and getting heads.

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 rolling a 3 on a 6-sided die?

Back

The probability is 1/6, since there is one favorable outcome (rolling a 3) out of six possible outcomes.

Front

If there are 3 red balls and 2 blue balls in a bag, what is the probability of picking a red ball?

Back

The probability is 3/5, since there are 3 favorable outcomes (red balls) out of 5 total balls.

Front

What is a sample space in probability?

Back

A sample space is the set of all possible outcomes of an experiment.