Today, we are going to explore some written methods for multiplying.
In Year 3, you would have looked at multiplying 2 digits by 1 digit.
e.g. 24 x 3
To help our understanding of multiplying numbers which are greater than our times table knowledge, we are going to partition the 2 digit number and then multiply both the multiples of 10 and the ones by the other number, which is 3 in this case.
so 24 x 3 becomes.
20 x 3 added to 4 x 3.
2 x 3 is 6, so 20 x 3 is 60 add to 4 x 3 which is 12
so 24 x 3 is 60 add 12, which is 72
We can show this on a place value grid or with a part, part, whole model. These are shown and explained on the video below. You can draw these in your workbook or if you like to print out, please see the links below.