A divisibility rule is a simple way to determine whether a given integer is completely divisible by a certain divisor by examining its digits.

By following certain rules, you can quickly determine the divisor of the given integer.

1) Divisibility test for 2:

The last digit should be even.

Example:

64, 586, 988, 7234

As you can see, unit digit of above examples are even numbered and they all are divisible by 2.

2) Divisibility Test for 3:

Add all digits and see if the given integer is divisible by 3.

Example:

1) 349 = 3+4+9=16

16 is not divisible by 3. Hence 349 is not divisible by 3.

2) 5433 = 5+4+3+3 =15

15 is divisible by 3. Hence 5433 is divisible by 3.

3) Divisibility Test for 4:

See if last two digits are divisible by 4.

Example:

1) 89032

As you can see the last 2 digits are divisible by 4. Hence 89032 is divisible by 4.

2) 1001

In this example, last two digits are not divisible by 4. Hence 1001 is not divisible by 4.

4) Divisibility Test for 5:

To determine whether the given integer is divisible by 5 or not, just check the last digit. The last digit should be either 5 or 0.

Example:

9990, 725, 2300, 6265

5) Divisibility Test for 6:

Here, you have to check test for both 2 and 3. That is the integer should be divisible by both 2 and 3.

Example:

3918

The above integer is divisible by both 2 and 3. Hence it is divisible by 6 also.

6) Divisibility Test for 8:

Here, last three digits should be divisible by 8.

Example:

1) 94864

In the above example, last three digits are divisible by 8. Hence the given integer is divisible by 8.

2) 35948

In the above example, last three digits are not divisible by 8. Hence the given integer is not divisible by 8.

7) Divisibility Test for 9:

If the sum of the digits is the multiple of 9, then the integer is divisible by 9.

Example:

1) 6678

6+6+7+8 = 27

27 is the multiple of 9. Hence 6678 is divisible by 9.

2) 983

9+8+3 = 20

20 is not divisible by 9. Hence 983 is not divisible by 9.

Thanks for reading!