Best Answer

There are 2 ways to do this.

Way 1:

Here's a simple way, based on the fact that 8 = 23; that is, 2 x 2 x 2.

Divide the number in question by 2 three times in a row. If you can divide it evenly by 2 each time (if every result is a whole number), then the number is evenly divisible by 8. If not, it's not. (Hint: Of course, if you start with or get to an odd number before the three divisions, it's not divisible evenly by 2, so you're done.)

Examples:

(1) Is 1,976 evenly divisible by 8?

1,976/2 = 988 (whole & even). 988/2 = 494 (whole & even). 494/2 = 247 (whole).

So 1,976 IS evenly divisible by 8.

(2) Is 2,444 evenly divisible by 8?

2,444/2 = 1,222 (whole & even). 1,222/2 = 611 (whole, but odd). You're done; 611/2 = 305.5 (fractional).

So 2,444 is NOT evenly divisible by 8!

Way 2:An alternative way is to divide the last three digits of a big number to see if it's divisible by 8. Example: 127398512

512 is divisible by 8.

It can be hard to memorize all the multiples of 8, so instead you can multiply the first digit by four and then subtract it from the last 2. I just found this out by messing around.

Example: 472

4 x 4 = 16

72 - 16 = 56

Since 56 is divisible by 8, 472, 23478, 23232324472, and7823728372472 are all divisible by 8.

If you subtract the product of the first digit and 4 from the last two digits and you get a negative number, divide the numbers riciprocal by 8. If the answer is rational, it works.

Example 512

4 x 4 = 20

12 - 20 = -8

riciprocal of -8 is 8

8/8 = 1

512 is divisible by 8.

Q: How do you know if a number is divisible by 8?

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If you have a few different numbers that you are using, divide them each by 8 and if you get a whole number, that number is divisible. If you are trying to figure out what is divisible by 8, you can use a divisibility test.A number is divisible by 8 if:the number formed by the last three digits is divisible by 8.So, an example of this would be:7, 120.This number is divisible by 8 because 120 (the last 3 digits) is divisible by 8!

If the last 3 digits are divisible by 8, the number is divisible by 8.

If the number formed by the last three digits is divisible by 8. Alternatively, if the number is divisible by 2, the quotient is divisible by 2 and that quotient is divisible by 2.

If it is an even number. 2, 4, 6, 8 etc.

Because 8 is 2 cubed, you can test if a number is divisible by 8 by dividing it by 2 three times. If the number you reach is an integer, then the number is divisible by 8. For example, 72/2 = 36/2 = 18/2 = 9. Therefore, 72 is divisible by 8. For very large numbers, if the last three digits are divisible by 8, the number itself is divisible by 8.

Related questions

Numbers are divisible by 8 if the number formed by the last three individual digits is evenly divisible by 8. For example, the last three digits of the number 3624 is 624, which is evenly divisible by 8 so 3624 is evenly divisible by 8.

If you have a few different numbers that you are using, divide them each by 8 and if you get a whole number, that number is divisible. If you are trying to figure out what is divisible by 8, you can use a divisibility test.A number is divisible by 8 if:the number formed by the last three digits is divisible by 8.So, an example of this would be:7, 120.This number is divisible by 8 because 120 (the last 3 digits) is divisible by 8!

If the last 3 digits are divisible by 8, the number is divisible by 8.

you can divide it by eight and it comes out even

If the last three digits of a number are divisible by 8, the whole number is divisible by 8.

a number is divisible by two if it ends in zero or an even number like 2, 4, 6 or 8

There is no smallest number since if any number is divisible by 8, then 8 less than that number is also divisible by 8 - and that argument continues all the way to minus infinity!The smallest positive number divisible by 8 is 8, itself.

If it is an even number. 2, 4, 6, 8 etc.

4 is divisible by 1, 2 and 4. So is 8. If a number is divisible by 8, it will also be divisible by 4.

The easiest way to know if a number is divisible by 9 is to add the digits in the number. 4 + 7 + 8 + 8 = 27 Since 9 will go into 27 evenly, 4788 is divisible by 9.

If the number formed by the last three digits is divisible by 8. Alternatively, if the number is divisible by 2, the quotient is divisible by 2 and that quotient is divisible by 2.

i do not know but i think it 480