GCSE Maths Multiplication - 2 Easy Methods
Introduction
There are a number of techniques that you can use when it comes to gcse maths multiplication and the main two techniques that we will discuss in this article is the column method and also the grid method.
Long Multiplication – Method 1
Just as you will perform addition and subtraction you need to write your numbers in the columns as per the rules of place value.
Suppose we want to multiply the following two numbers together 353 \times 16. The first instance we would write our calculation as follows:
\begin{array}{r} 353 \\ \times 16 \\ \hline \end{array}What you are essentially doing is multiplying 353 with 10 and then with 6. You can do this in any order. Let us start with the 6.
So, multiplying 353 with 6 gives the following:
\begin{array}{r} 353 \\ \times 16 \\ \hline 2118 \end{array}Next let us multiply the 353 with 10 which will give the following:
\begin{array}{r} 353 \\ \times 16 \\ \hline 2118 \\ 3530 \end{array}All that is left to do is to add the numbers 2118 and 3530 together and this will give the following final answer:
\begin{array}{r} 353 \\ \times 16 \\ \hline 2118 \\ +3530 \\ \hline 5648 \end{array}GCSE Maths Multiplication - The Grid Method
The idea here is to break the numbers down into hundreds, tens, units.
So 353 is 300 + 50 + 3 and 16 is 10 + 6 and we set this up as a grid as follows:
We then multiply each number in the together and this will give the following:
To find the answer we just add up all the numbers within the grid as follows:
3000+500+30+1800+300+18=5648And this gives the same answer as before.
There is no better method. It is all about what you are most comfortable with but whichever method you use, you need to know your multiplication tables.
GCSE Maths Multiplication Exam Questions
1
When you are doing your GCSE Multiplication Maths revision for your final exams, whether foundation or higher, and you see the sentence “you must show all your working” then you cannot just write down the answer, no matter how simple you think the question is. As a rule of thumb, you should always show your working, in case you make any mistakes and are still able to pick up method marks.
Here is the working for this question using the grid method for multiplication but you will obtain the same answer using the standard column method.
\begin{array}{c|c|c|c} x & 300 & 60 & 2 \\ \hline 50 & 15000 & 3000 & 100 \\ \hline 4 & 1200 & 240 & 8 \end{array}15000+3000+100+1200+240+8=195482.
Here we need to do the following calculation: 6.79 \times 28
If you are without a calculator and you need to multiply a decimal then you need to initially ignore the decimal. Treat the question as though it were 67928 which we will now work out using the column method as follows:
\begin{array}{r} 679 \\ \times 28 \\ \hline 5432 \\ +13580 \\ \hline 19012 \end{array}Now we need to go back to the original question which is 6.79 \times 28
You will see that there are two numbers that appear after a decimal point and so we need a total of two numbers that appear after the decimal point in our answer.
This means that the final answer will be £ 190.12
3.
Here you are asked to find the “total” amount of money. To do this you are needing to perform a gcse maths multiplication of 27 \times 55 which we will calculate using the column method:
\begin{array}{r} 27 \\ \times 55 \\ \hline 135 \\ +1350 \\ \hline 1485 \end{array}So the amount of money raised is £ 1485
Provided that you know all your multiplication tables then there should be no issues with this topic. Whichever technique you understand and you feel comfortable with, then stick with it. There is no need to ever switch from one method to another and no question will ever ask you to use one method over the other. However, it should be important to note that you should be aware of both GCSE multiplication techniques. This is because you do get questions asking you to spot a mistake that a student has done within a question. If it is for multiplication it could be either spotting a mistake using the column method or the grid method.