# common denominator for 7 and 9

#### Understand the Problem

The question is asking for the least common denominator of the numbers 7 and 9, which is the smallest multiple that both numbers share. To find this, we typically look for the least common multiple (LCM) of the two numbers.

$63$

The least common denominator (LCM) of 7 and 9 is $63$.

#### Steps to Solve

1. Identify the multiples of each number

First, we need to find the multiples of both numbers, 7 and 9.

Multiples of 7: $7, 14, 21, 28, 35, 42, 49, 56, 63, 70, 77, 84, 91, 98, 105, \ldots$

Multiples of 9: $9, 18, 27, 36, 45, 54, 63, 72, 81, 90, 99, 108, \ldots$

2. Find the common multiples

Now we look for the numbers that appear in both lists of multiples.

Common multiples of 7 and 9: $63, 126, 189, \ldots$

3. Identify the least common multiple (LCM)

The least common multiple is the smallest number that is a common multiple of both numbers.

From our list, the smallest common multiple is $63$.

The least common denominator (LCM) of 7 and 9 is $63$.