In this section we will look at how we calculate the probabilities of single events.
Probabilities are always between 0 and 1, and can be written as fractions, decimals or percentages.
In this section we will write all probabilities as fractions.
We are only going to look at cases where all the possible outcomes are equally likely, like rolling a fair dice.
On a fair or unbiased dice, the six possible outcomes each have the same chance of occuring  they are equally likely.
The words "fair" or "unbiased" mean that all outcomes are equally likely. 
To find the probability of a particular event, we use this formula:
Example 1
Imagine we are rolling a fair dice. There are six equally likely outcomes: 1, 2, 3, 4, 5 and 6.
(a) What is the probability of getting a five?
In this case there is only one successful outcome, 5.
(b) What is the probability of getting an even number?
In this case there are 3 successful outcomes, which are 2, 4 and 6.
(c) What is the probability of getting a four or a five?
In this case there are 2 successful outcomes, which are 4 and 5.
Notice that we simplify the fractions in the answers where it is possible to do so.
Example 2
A bag of sweets contains 6 mints and 4 eclairs. One sweet is taken at random from the bag.
In this case there are ten equallylikely outcomes: six mints and four eclairs.
(a) What is the probability of picking a mint?
As there are six mints in the bag, there are six successful outcomes.
(b) What is the probability of picking an eclair?
As there are four eclairs, there are four successful outcomes.
(1) A spinner with five equally likely outcomes is spun. The outcomes are 1, 2, 3, 4 and 5.
(a) What is the probability of getting a two?
(b) What is the probability of getting an even number?
(2) The spinner is now altered to show the numbers 1, 2, 2, 2 and 4.
(a) What is the new probability of getting a two?
(b) What is the new probability of getting an even number?
Most of the answers in this section are fractions. Each fraction has two input boxes. Put the numerator in the top box and the denominator in the bottom box, like this: 
