A number is divisible by 8 if its last three digits are divisible by 8, or if the last three digits are zeros.
Understanding the Divisibility Rule of 8
The divisibility rule for 8 provides a quick way to determine if a larger number is divisible by 8 without performing long division. The rule focuses on the last three digits of the number.
How to Apply the Rule:
- Identify the last three digits: Take the number you want to check and focus only on the last three digits.
- Check for divisibility by 8: Determine if this three-digit number is divisible by 8. You can do this through division or by recognizing multiples of 8.
- Result: If the three-digit number is divisible by 8, then the original number is also divisible by 8. If the last three digits are all zeros, the number is also divisible by 8.
Examples:
- 123872: The last three digits are 872. 872 / 8 = 109. Therefore, 123872 is divisible by 8.
- 4000: The last three digits are 000. Since they are all zeros, 4000 is divisible by 8.
- 954621: The last three digits are 621. 621 / 8 = 77.625 (not a whole number). Therefore, 954621 is not divisible by 8.
Multiple sources confirm this rule: Cuemath, Byju's, Unacademy, and GeeksforGeeks all state that a number is divisible by 8 if its last three digits are divisible by 8 or are zeros.
