This trick has been widely taught to facilitate getting the multiplication and this trick only applies to the multiplication 6 to 10 only. For more details can be seen from the examples below.
Here is a marker of the finger from 6 to 10 to keep in mind.
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1)
6 × 6 = ???
Finger symbol for multiplication is as follows:
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This means:
2 fingers closed = 20.
4 finger open left and right finger open 4 = 4 x 4 = 16
Next we add 20 + 16 = 36
So the product of 6 x 6 = 36
Finger symbol for multiplication is as follows:
2 fingers closed = 20.
4 finger open left and right finger open 4 = 4 x 4 = 16
Next we add 20 + 16 = 36
So the product of 6 x 6 = 36
2)
7 x 8 = ???
7 x 8 = ???
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5 fingers closed = 50.
3 fingers open left and right fingers open 2 = 3 x 2 = 6
Next we add 50 + 6 = 56
So the product of 7 x 8 = 56
3)
6 x 9 = ???
6 x 9 = ???
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5 fingers closed = 50.
3 fingers open left and right fingers open 2 = 3 x 2 = 6
Next we add 50 + 6 = 56
So the product of 7 x 8 = 56
3)
6 x 9 = ???
6 x 9 = ???
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This means:
7 covered finger = 70.
2 fingers open and one finger left open right = 2 x 1 = 2
Next we add 70 + 2 = 72
So the product 8 x 9 = 72
Can try try for other multiplication.
7 covered finger = 70.
2 fingers open and one finger left open right = 2 x 1 = 2
Next we add 70 + 2 = 72
So the product 8 x 9 = 72
Can try try for other multiplication.