To determine if a number is divisible by 8, you only need to check the last three digits of that number. If these last three digits form a number that is divisible by 8, then the whole number is also divisible by 8.
For example, consider the number 12,456. Look at the last three digits, which are 456. Now, divide 456 by 8:
456 ÷ 8 = 57
Since 57 is a whole number, we can say that 456 is divisible by 8, and consequently, 12,456 is also divisible by 8.
On the other hand, if we take the number 12,345. The last three digits are 345. When we divide 345 by 8:
345 ÷ 8 = 43.125
Since this does not result in a whole number, we can conclude that 12,345 is not divisible by 8.
In summary, just remember to focus on the last three digits of any number when checking for divisibility by 8. If that three-digit number is divisible by 8, then the entire number is as well.