Why is it useful to know the divisibility of a number? It allows us to determine whether a number is divisible by another number without having to divide them. In this post, we are going to learn **the ****divisibility guidelines for 9.**

**Criteria for divisibility by 9: **

**A number is divisible by 9 if the sum of its digits is 9 or a multiple of 9. **

For example:

#### is 2610 divisible by 9?

In order to find out **we add its digits:**

2+6+1+0=9

Therefore 2610 is divisible by 9.

Another example:

#### is 965 divisible by 9?

We add all the digits:

9+6+5=20

Since 20 is not divisible by 9, then 965 is not divisible by 9.

To keep learning:

Divisibility guidelines for:

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Learn More:

- Divisibility Guidelines for 6 and Some Examples
- Divisibility Guidelines for 6, 8 and 12
- Divisibility Guidelines for 2, 5, and 10
- Divisibility Guidelines for 7 and Some Examples
- Follow the Divisibility Guidelines for 3