Tag: halving

Year 3 maths worksheet: Halving

Here is a page for checking understanding of halving. The numbers to halve are all multiples of 10 so it is important that children are confident with halving numbers up to 20 before trying this. By Year 3 children should be knowing these halves off by heart.

The questions with a whole ten answer are very straightforward. The tricky bit is halving a number such as 70. Probably the best approach to begin with is to split the 70 into 60 and 10. Halve the 60 (that’s 30) and halve the 10 (that’s 5) and add the 30 and 5 to make 35.

After a while this will become second nature as the process is mentally ‘internalised’.

This can be found in our Year 3 Calculating category.

Half of multiples of 10

Year 4 maths worksheet: Doubling and halving

It’s always a good idea to think about how we work out answers in our heads and doubling multiples of 5 is a good example of this. Thinking and saying what you do is similar to watching  a slow motion movie, in real time everything happens very quickly but by slowing it down each step can be seen in turn.

Let’s look at doubling 65. I know without thinking that double 5 is 10, so I ignore this part and first work out double 60. This is 120. I then add on 10 for the double 5 part, making 130.

A similar process can be used with halving a number such as 130. I take 10 off to make 120 as it is easy to work out half of 120, which is 60. I then add on 5 (which is half of the 10 I took off at the start) making 65.

Try to get children to explain how they do these doubling and halving questions.

This page can be found in the year 4 worksheets section.

Double multiples of 5