This way i search in google but find only with fingers. Maybe this my discoveries :D

The easiest way to calculate 9x with - :

1x9=9 (10-1=9)

2x9=18 (20-2=18)

3x9=27 (30-3=27)

4x9=36 (40-4=36)

5x9=45 (50-5=45)

6x9=54 (60-6=54)

7x9=63 (70-7=63)

8x9=72 (80-8=72)

9x9=81 (90-9=81)

10x9=90 (100-10=90)

11x9=99 (110-11=99)

12x9=108 (120-12=108)

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14365x9=129285 (143650-14365=129285)

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Who know this way, comment.

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## 4 Discussions

4 years ago on Introduction

any 2 digits X11 as follow: 54X11 =5(5+4)4 =594. 23X11= 2(2+3)3 = 253. For digits that = more than 10 like 47 or 98 do as follow: 47X11 = 4(4+7)7 = 4(11)7 = (4+1)17 so it would be 517. 98 would be 9(9+8)8 =9(17)8 = (9+1)78 =1078

NOTE: I have used = where I should not have.

If you want to X5 then X10 and then divide by 2. 5 = 10/2. like 480 X 5 = 4800/2 = 2400

4 years ago

Wow, never thought of it that way...

4 years ago on Introduction

fur numbers up to 10, I learnt to do it on my figures...

start from the left, and put down the figure for the multiplication your doing (so for 3, its your left middle finger) the fingers on the left are your 10's and on the right are your units...

4 years ago on Introduction

the way i learned the 9 times tables is is to take 1 away from the number you multiply times nine for the tens position then nine minus the tens position for the ones position

for example ... 9 x 2 = 2-1 is 1(the one goes in the tens column) 9-1 is 8 (the eight goes in the ones column)

unfortunately that method only work up until 10 .. your system is more flexible