Probability using Fractions, Percents, and Decimals

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 will not happen and 1 means it will definitely happen.

Front

How do you calculate the probability of a simple event?

Back

To calculate the probability of a simple event, divide the number of favorable outcomes by the total number of equally likely outcomes.

Front

If there are 20 equally likely outcomes and 5 of them are favorable, what is the probability?

Back

The probability is 5/20 or 1/4.

Front

What is the probability of rolling a 3 on a standard six-sided die?

Back

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

Front

Convert the fraction 1/4 to a percent.

Back

1/4 as a percent is 25%.

Front

Convert the decimal 0.75 to a fraction.

Back

0.75 as a fraction is 3/4.

Front

What is the probability of flipping a coin and getting heads?

Back

The probability is 1/2, since there are two equally likely outcomes (heads or tails).

Front

If the probability of an event is 0.2, what is the percent chance of it occurring?

Back

The percent chance is 20%.

Front

What does it mean if an event has a probability of 0?

Back

It means the event is impossible and will not occur.

Front

What does it mean if an event has a probability of 1?

Back

It means the event is certain and will definitely occur.