Mark Symmonds – Chatsworth International School, Singapore

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Mark Symmonds – Chatsworth International School, Singapore

Just like when we count, start from the left.

1, 2, 3, 4, 5, 6…

As we are looking for 3 multiplied by 9 we count across to our 3rd finger and move it down.

1

23

Marker Finger

3 x 9 =3 x 9 =1 x 9 = 92 x 9 = 183 x 9 = 274 x 9 = 365 x 9 = 45

Marker Finger

7 x 9 =7 x 9 =1 x 9 = 92 x 9 = 183 x 9 = 274 x 9 = 365 x 9 = 456 x 9 = 547 x 9 = 638 x 9 = 729 x 9 = 8110 x 9 = 90

Marker Finger

9 x 9 =9 x 9 =1 x 9 = 92 x 9 = 183 x 9 = 274 x 9 = 365 x 9 = 456 x 9 = 547 x 9 = 638 x 9 = 729 x 9 = 8110 x 9 = 90

1 x 9 = 92 x 9 = 183 x 9 = 274 x 9 = 365 x 9 = 456 x 9 = 547 x 9 = 638 x 9 = 729 x 9 = 8110 x 9 = 9011 x 9 = 9912 x 9 = 108

Remember there are no tens digit in 1 x 9 as the answer is 0 tens and 9 units!

The tens digit is always one less than the number you are dividing!

This pattern only works up until 10 x 9

1 x 9 = 92 x 9 = 183 x 9 = 274 x 9 = 365 x 9 = 456 x 9 = 547 x 9 = 638 x 9 = 729 x 9 = 8110 x 9 = 9011 x 9 = 9912 x 9 = 108

9 added to nothing equals 9

If you add both the digits of the answer together they will always equal 9.

The tens column in the answer is always one less than the one you are multiplying.

So if we take 7 x 9…

We know the answer will start with?

So we know that the answer is 63.

And the two digits added together make nine so 6 and what make 9?

3

6

so…so…

19801980

so…so…

so…so…

54455445

so…so…

so…so…

1217712177

so…so…

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