Part 08 · Probability and statistics · Card 1 of 8
Probability scale
A number from 0 to 1 showing how likely something is. 0 means impossible, 1 means certain and 1/2 means even chance.
Last updated
Analogy
Like a weather forecast dial from 'never' to 'definitely'.
Example
Fair six-sided dice
P(6) = 1/6P(even) = 3/6 = 1/2P(7) = 0
In practice
A 0.2 chance of rain means rain is unlikely but possible.
Practice
Flashcards
- What is the probability of an even number on a fair dice?1/2, since 3 of the 6 numbers are even.
Questions people ask
How do you work out a probability?
Divide the number of ways your event can happen by the total number of equally likely outcomes. For rolling an even number on a dice, there are 3 even numbers out of 6, so the probability is 3/6 = 1/2.
Can a probability be bigger than 1?
No. A probability of 1 means the event is certain. You cannot be more than certain. Probabilities run from 0 to 1, as a fraction, decimal or percentage. If you get an answer over 1, you have made an error.