Number KS3 Maths Worksheets, Questions and Revision

Write 252 as a product of its prime factors, giving your answer in index form.

1. Divide by the smallest prime, 2: 252 / 2 = 126.
2. Divide by 2 again: 126 / 2 = 63.
3. 63 is not divisible by 2, so try 3: 63 / 3 = 21.
4. Divide by 3 again: 21 / 3 = 7.
5. 7 is itself prime, so stop. Collecting the factors gives 252 = 2 x 2 x 3 x 3 x 7, so in index form 252 = 2^2 x 3^2 x 7.