This is an interesting discovery. In this tutorial on Mathematical shortcuts, we will see how to remember the tables of 9. You will see at the end of this tutorial, you can easily memorize the tables of 9 and the tables of the numbers which is a sequence of 9’s like 99, 999, 9999 and so on.
Remember the multiplication tables of 9
Let us begin with the tables of 9. I think there is no shortcut here. Lot of us already know the tables by heart.

Tables
Product
9 x 1
0 9
9 x 2
1 8
9 x 3
2 7
9 x 4
3 6
9 x 5
4 5
9 x 6
5 4
9 x 7
6 3
9 x 8
7 2
9 x 9
8 1
9 x 10
9 0
The important thing in memorizing the multiplication tables is understanding the pattern in the tables :
 Notice that the sum of the numbers is always 9. (Digital Root)
 Notice that products. It comprises of 2 digits. The unit digit starts from 9 and reduces to 0. Whereas, the 10’s digit starts from 0 and go upto 9.
If you donot know the tables of 9, please memorize it by understanding the patterns. By just remembering the tables of 9, you can easily replicate the tables of 99, 999, 9999 and so on.
Remember the multiplication table of 99
Now, let us consider the table of 99. You can easily replicate the tables of 99, by just inserting a 9 in between the digits of the tables of 9.
So, just separate the digits of the product and put a single 9 in between and you have the tables of 99.

Tables
Product
Product
99 x 1
0 _ 9
0 9 9
99 x 2
1 _ 8
1 9 8
99 x 3
2 _ 7
2 9 7
99 x 4
3 _ 6
3 9 6
99 x 5
4 _ 5
4 9 5
99 x 6
5 _ 4
5 9 4
99 x 7
6 _ 3
6 9 3
99 x 8
7 _ 2
7 9 2
99 x 9
8 _ 1
8 9 1
99 x 10
9 _ 0
9 9 0
Very easy right ðŸ™‚
Memorize the tables of 999
Now, let us consider the table of 999 and beyond. You can easily replicate the tables of 99, by just inserting 2 9’s in between the digits of the tables of 9.
So, just separate the digits of the product and put two 9’s in between and you have the tables of 999.

Tables
Product
Product
999 x 1
0 _ _ 9
0 9 9 9
999 x 2
1 _ _ 8
1 9 9 8
999 x 3
2 _ _ 7
2 9 9 7
999 x 4
3 _ _ 6
3 9 9 6
999 x 5
4 _ _ 5
4 9 9 5
999 x 6
5 _ _ 4
5 9 9 4
999 x 7
6 _ _ 3
6 9 9 3
999 x 8
7 _ _ 2
7 9 9 2
999 x 9
8 _ _ 1
8 9 9 1
999 x 10
9 _ _ 0
9 9 9 0
Very easy right ðŸ™‚
Similarly, you can easily obtain the multiplication table of 9999 by inserting 3 9’s in between the digits of multiplication 9 table.
I hope you find the tutorial very useful. Please leave a comment or contact me, if you have any doubts or any comments on this topic. I would be glad to answer.