What are Prime Numbers?
Prime numbers by definition are numbers that cannot be divided by any other number but itself and 1. For e.g. 2 is a prime as it can only be divided by 2 and 1 and nothing else. One thing to note is that 1 does not count as a prime number.

The Factor Tree
Therefore, we need to work out which primes, when multiplied together, will give 120 as an answer. The best way to approach this style of question is by drawing a factor tree.

For the first level of the tree we want a prime number when multiplied by another number (not necessarily another prime) will give you 120. You must make sure that at each level of the tree you have at least one prime number.

Then you continue to simplify at each level of the tree. So in this instance, you need two numbers (at least one should be a prime) that multiply to make 60.

Continue this process until you are left with two remaining primes at the end of the tree.

Therefore, 120 is the product of 2 x 2 x 2 x 3 x 5.

Solve the simultaneous equations: x2 + y2 = 20, 3x=2-y

Related Maths GCSE answers

What is 125^(-2/3)?

Simplify: 5a + 2 – a + 9

Solve the simultaneous equations: 2x+y=18 and x-y=6

Write 120 as a product of its prime factor