This trick is an alternative method for multiplying two single digit numbers from 9 to 5. It assumes the user can multiply single digit numbers up to 4.

Here is how it works:

List 9 to 5 in two lines.

Underline the numbers one wants to multiply

Everything in the column under the line is worth ten

Every digit in the column above the lines are counted.

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## BMAD

This trick is an alternative method for multiplying two single digit numbers from 9 to 5. It assumes the user can multiply single digit numbers up to 4.

Here is how it works:

List 9 to 5 in two lines.

Underline the numbers one wants to multiply

Everything in the column under the line is worth ten

Every digit in the column above the lines are counted.

Multiply the counted digits.

Add the tens to the products of the digits

Voila

Why does this work?

For example:

9 x 7

9 9

_ 8

8 7

7 _

6 6

5 5

1d 3d

_

10

10 _

10 10

10 10

60 + 1 x 3 = 63

------------------------

6x5

9 9

8 8

7 7

6 6

_ 5

5 _

4d 5d

_

10

10 + 4 x 5 = 30

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