## Sunday, 20 July 2008

### Divisibility Rules - Interesting Maths Concept

Everyone has for some instances want to know if an integer can be divided by another (without giving a remainder). Is there a way? Yes, there is.

Listed below are some interesting methods to check whether integer can be divided by another integer. These wonderful technique is called "Divisibility Rules". They are a set of checking rules to quickly identify divisibility.

Here we go .......

Dividing by Two
Look at the last digit. Is it even or odd? If it is odd, the integer cannot be divided by two.

Dividing by Three
Sum up all the digits within the integer. If the sum is divisible by 3, the original integer can then be divided by 3.

Dividing by Four
Look at the last 2 digits and see if they can be divided by 4. If yes, then the original integer can be divided by 4.

Dividing by Five
If the last digit of the integer is 0 or 5, the original integer can be divided by 5.

Dividing by Six
If the integer can be divided by BOTH 2 and 3, then the original number can be divided by 6.

Dividing by Seven
Double (times two) the last digit of the integer and subtract the doubled number from the leftover (original taking away the last digit) in the original. Check whether the result can be divided by 7. If unsure, you can reapply the "divide by 7" rule to the new result obtained to check whether the original integer can be divided by 7.

Dividing by Eight
Check whether the last 3 digits of the integer can be divided by 8. If it can, the original integer can then be divided by 8.

Dividing by Nine
Sum up all the digits within the integer. If the final sum can be divided by 9, then the original integer can be divided by 9.

Dividing by Ten
If the last digit of the integer is 0, then the integer can be divided by 10. This is easy!

With all the rules above, you can impress anyone with your dividing skill.
But note of caution..... YOU WILL BE BUSY entertaining questions!

:-)