Shortcuts for Divisibility by 5, 6 , 8 and 9

Few shortcuts to help you work smartly and save time

Divisibility by 5:
How to check a number is divisible by 5?
It is very simple, check for units digit, if it is either 5 or 0, then clearly the number is divisible by 5.

Examples:
Is the number 13356890 divisible by 5?
Check the units digit in the given number
unit digit is 0, so 13356890 is divisible by 5.

Is the number 56722368553 divisible by 5?
The units digit is not 0 or 5, so the number 56722368553 is not divisible by 5.

Divisibility by 6:
How to check a number is divisible by 6?
It is very simple, check the number is divisible by 2 and 3, if it is divisible by both, then clearly the number is divisible by 6.

Examples:
Is the number 3246546 divisible by 6?
First check the number is divisible 2,
its unit digit is 6, which is divisible by 2.
Then check the number is divisible 3 also,
3 + 2 + 4 + 6 + 5 + 4 + 6 = 30
30 is divisible by 3, so the number is also divisible by 3
The number 3246546 is divisible both by 2 and 3, so it is divisible by 6.

Is the number 128956 divisible by 6?
Its unit digit is 6, which is divisible by 2.
Now check the number is divisible 3 also,
1 + 2 + 8 + 9 + 5 + 6 = 31
31 is not divisible by 3, so the number is not divisible by 3
The number 128956 is divisible only by 2 and not by 3, so it is not divisible by 6

Divisibility by 8:
How to check a number is divisible by 8?
It is very simple, check whether the last three digits of the number is divisible by 8, if it is, then the number is divisible by 8.

Examples:
Is the number 7377473496 divisible by 8?
Take the last three digits of the number.
Last three digit is 496, check whether it is divisible by 8.
496 is divisible by 8, So the number 7377473496 is divisible by 8.

Is the number 546632318 divisible by 8?
The last three digit is 318.
318 is not divisible by 8, so the number 546632318 is not divisible by 8.

Divisibility by 9:
How to check a number is divisible by 9?
It is very simple, first sum all the digits of the number, now check whether the result is divisible by 9. If the answer is divisible by 9, clearly the number will be divisible by 9. It is similar to divisibility of 3.

Examples:
Is the number 57225834 divisible by 9?
Now, sum the digits of the number,
5 + 7 + 2 + 2 + 5 + 8 + 3 + 4 = 36
36 is divisible by 9, so 57225834 is divisible by 9.

Is the number 3216763132 divisible by 3?
3 + 2 + 1 + 6 + 7 + 6 + 3 + 1 + 3 + 2 = 34
34 is not divisible by 9, so the number 3216763132 is not divisible by 9.

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