Learning the table of nine by heart
Learning the table of nine is not difficult if you know the tricks to find the right answer. You can find the solution of every multiplication with nine by using your ten fingers or with a simple calculation trick.
The trick with your fingers
The first trick is a counting trick and is as follows: first bend the finger with which you want to multiply nine, count from the left to come to the right finger. Then you count all fingers to the left of the bent finger. You will then find the first digit of the answer. The second digit of the solution is then the number of fingers to the right of the bent finger.
For example: How do you calculate 4×9?
You now bend the fourth finger from the left. This is the forefinger of your left hand. I count three fingers to the left of the forefinger and 6 fingers to the right of the forefinger. The correct number is then: 36. 4×9 = 36.
If you do not want to work with fingers, you can put ten lines on a piece of paper and then count from the left to the correct dash that you want to multiply by nine. Then you count the number of dashes left and right of this dash, and you have the answer.
The trick with subtraction sums
Another trick is a calculation trick with subtraction sums and goes as follows: First, you calculate the first digit by subtracting the number you want to multiply by one. After that, the second number equals to the number when you deduct 10 with the number that you want to multiply with.
A calculation example with 6×9
The first sum is 6-1, and therefore the first digit is equal to 5. The second sum is 10-6, and this is equal to 4. The result of 6×9 is then equal to 54.
Bear in mind that these tricks only apply to the first ten numbers multiplied by 9. For higher quantities, you first have to split the amount by which you multiply by nine and then add up the answers. How this works, I explain to you in another blog.
You can find more tricks to learn the tables by heart in our fun app “the twelve times tables” With this app, you learn all the skills to learn the first twelve tables by heart quickly. This app has several educational math exercises, which you can easily exercise on your own without help.
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