Math Dictionary / Probability

Probability

Probability measures how likely an event is to happen.

StatisticsGrade 6Grade 7Grade 8GEDSATACT

What it means

It is often written as favorable outcomes divided by total possible outcomes.

Also called: chance

Examples

P(heads) = 1/2 for a fair coin
P(rolling a 3) = 1/6
Probability ranges from 0 to 1

Common mistake

A probability cannot be less than 0 or greater than 1.

Try one

Question: What is the probability of choosing a vowel from A, B, C, D, E?

Show answer

There are 2 vowels out of 5 letters, so the probability is 2/5.

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