How To Teach Subtraction
Question
When using a number line the minus sign means you will calculate to the
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Hi, I am Donald Sinclair. I am a Science and Math tutor with Greater London Tutors. Today, we are going to be looking at how to teach various topics. The basic way to teach subtraction is to do the old task, if I have so many apples and take some many away, how many will I have left. So if you want to do this on, seven minus three, encourage the child to think of seven apples, let's say and what would happen if you take three of them away. If three of them are eaten, how many will be left. Then they can picture that in their head and remove three of them, they should have a clear picture of what is left. And they should know that seven minus three equals four. Once the child has the basic idea of simple subtraction, you can encourage them to think about the idea that subtraction is the inverse of addition. In the other words, doing just the opposite what addition does. So if you have to ask what five plus three equals, hope they will be able to tell that equals eight. They you can introduce this idea. Five plus what equals eight. Now if you done just the previous example, they should immediately able to tell you, three goes in here. Then you have to give them an unknown example. You have to ask them what eight plus what equals 11. Then hopefully at this point, they were able to fill the missing number. You can tell them that question mark replaced by three to complete the sum. Then you can show that subtraction is simply putting the unknown value on the other side of the equal sign. So here, when we had five plus what equals eight, we can right that eight minus five equals what? Now it will give you the exact same value, three. So here, this sum can be written as 11 minus eight equals three. The number line which can be used in addition can also be used in subtraction. Here the key idea is that the minus sign means you just need to be moving to the left rather than the right. So if you are doing sum eight minus five, start at eight and you move to the left five times. 1, 2, 3, 4, 5 and the number you end on is the answer to the sum. So in this case, it is three. A particularly bright child may ask what happens if we go to the left at the zero. If you like, at this point to, bring in the idea of the negative numbers. But to start with, I would stay stick with numbers that would get you positive numbers. These are some basic ideas on how to teach your child subtraction. .