Multiplication

If you are multiplying

by 10: put 0 on the end
by 100: put 2 zeros on the end
by 1000: put 3 zeroes on the end
and so on.

For example:

38 X 10 = 380
38 X 100 = 3800
38 X 1000 = 38000

When you’re working with large numbers – 10s, 100s or 1000s – you can make your calculations a lot easier by removing the zeros, completing your sum, and then adding the zeros back on again.

For example if you need to work out 6 x 1200, take off the two zeros, multiply 6 x 12 to make 72, and then add the two zeros again to make 7200.

An easy way to remember your 9 times table. As you work your way up the nine times table, the first number of each multiple increases by one, while the second number decreases by one.

For example, 2 x 9 = 18. 1 + 1 = 2

8 – 1 = 7

Put 2 and 7 together – 27 – and you’ve got the answer to 3 x 9.

2 + 1 = 3
7 – 1 = 6

Put 3 and 6 together – 36 – and you’ve got the answer to 4 x 9.

This rule works all the way up to 10 x 9.

An easy way to check your 9 times table is by adding the individual numbers of your answer together.

The individual numbers of every multiple of nine can be added together to make nine. E.g. 2 x 9 = 18, 1 + 8 = 9; 4 x 9 = 36, 3 + 6 = 9 and so on.

The 11 times table is the easiest one to remember – multiples of 11 are the number you have multiplied by written twice.

2 x 11 = 22
5 x 11 = 55
8 x 11 = 88
and so on.