Answer :
Final answer:
The divisibility rule for 9 requires that the sum of all digits of a number must be a multiple of 9, which is not the case for the number 118; therefore, 118 is not divisible by 9.
Explanation:
Divisibility Rule for 9
To determine if a number is divisible by 9, add up all its digits and see if the sum is a multiple of 9. For example, the number 118 has the digits 1, 1, and 8. Adding these digits together, we get 1 + 1 + 8 = 10. Since 10 is not a multiple of 9, 118 is not divisible by 9. The divisibility rule for 9 is helpful because it allows us to quickly assess divisibility without performing long division.
The key to understanding this concept is recognizing that the sum of the digits of a number is what determines its divisibility by 9. This rule is universally valid, just like any mathematics rule, and is simple enough to perform in your head.
