The rule is a method to multiplay any two digit nymber by 11, it is simple, easy to learn and very effecgtive.
Note: Only applies to 2 digit numbers
1. Choose a Number
> Eg. 45
2. Split the number into two
> Eg. 4_5
3. Add the two numbers
> Eg. 4_5 (4+5=9)
4. Put the number between the split nuymbers
> Eg. 495
5. You will get your final answer!!!
But if the sum is greater than nine;
We carryover the tens digit to left i.e. the third number (hundreds place)
For example:
> 65
> 6_5
>6_5 (6+5=11)
+1
>615
>715
Note: Only applies to 2 digit numbers
1. Choose a Number
> Eg. 45
2. Split the number into two
> Eg. 4_5
3. Add the two numbers
> Eg. 4_5 (4+5=9)
4. Put the number between the split nuymbers
> Eg. 495
5. You will get your final answer!!!
But if the sum is greater than nine;
We carryover the tens digit to left i.e. the third number (hundreds place)
For example:
> 65
> 6_5
>6_5 (6+5=11)
+1
>615
>715