Probability is usually written as a fraction.

On the top (numerator) of the fraction, we place the number of options we are looking for.

On the bottom (denominator) of the fraction, we place the total number of possible combinations.

Example

Look at these number cards.

What is the probability of selecting a number that is either even or greater than 8?

Answer

There are 8 options that we are looking for (these are 2, 4, 6 and 8 and 9, 10, 11 and 12)

There are 12 possible combinations.

The probability is 8/12 which reduces to 2/3

Let's have a go at the questions now.