Now multiply 86 by the reference number, 100, to get 8,600. Then we must multiply the numbers in
the circles: 8 times 6.
If we don’t know the answer, we can draw two more circles below 8 and 6 and make another
calculation. We subtract the 8 and 6 from 10, giving us 2 and 4. We write 2 in the circle below the 8, and
4 in the circle below the 6.
The calculation now looks like this:
We now need to calculate 8 times 6, using our usual method of subtracting diagonally. Two from 6 is
4, which becomes the first digit of this part of our answer.
We then multiply the numbers in the circles. This is 2 times 4, which is 8, the final digit. This gives
us 48.
It is easy to add 8,600 and 48.
8,600 + 48 = 8,
Here is the calculation in full.
You can also use the numbers in the bottom circles to help your subtraction. The easy way to take
from 94 is to take 10 from 94, which is 84, and add the 2 in the circle to get 86. Or you could take
from 92. To do this, take 10 from 92, which is 82, and add the 4 in the circle to get 86.
With a little practice, you can do these calculations entirely in your head.
Note to parents and teachers
People often ask me, ‘Don’t you believe in teaching multiplication tables to children?’
My answer is, ‘Yes, certainly I do. This method is the easiest way to teach the tables. It is the fastest way, the most painless way and
the most pleasant way to learn tables.’
And while they are learning their tables, they are also learning basic number facts, practising addition and subtraction, memorising
combinations of numbers that add to 10, working with positive and negative numbers, and learning a whole approach to basic
mathematics.