If a number is divisible by 9, what can be inferred about the sum of its digits?
Practice Questions
Q1
If a number is divisible by 9, what can be inferred about the sum of its digits?
It is even
It is divisible by 3
It is divisible by 9
It is a prime number
Questions & Step-by-Step Solutions
If a number is divisible by 9, what can be inferred about the sum of its digits?
Step 1: Understand what it means for a number to be divisible by 9. This means that when you divide the number by 9, there is no remainder.
Step 2: Learn about the sum of the digits of a number. For example, for the number 234, the sum of the digits is 2 + 3 + 4 = 9.
Step 3: Know the rule: If a number is divisible by 9, then the sum of its digits must also be divisible by 9.
Step 4: Check an example: Take the number 81. The sum of its digits is 8 + 1 = 9, which is divisible by 9. Therefore, 81 is divisible by 9.
Step 5: Remember that this rule works in the opposite direction too: If the sum of the digits of a number is divisible by 9, then the original number is also divisible by 9.
