The lowest common denominator (LCD) of two or more fractions is the smallest number that can serve as a denominator for all fractions involved. To find the LCD of 8 and 9, we need to determine the least common multiple (LCM) of the two numbers.
First, we list the multiples of each number:
- Multiples of 8: 8, 16, 24, 32, 40, 48, 56, 64, 72, 80, 88, 96, 104, 112, 120…
- Multiples of 9: 9, 18, 27, 36, 45, 54, 63, 72, 81, 90, 99, 108, 117, 126, 135…
By comparing both lists, we can see that the first common multiple is 72. Therefore, the least common multiple of 8 and 9 is 72. This means that the lowest common denominator of 8 and 9 is also 72.
In summary, the lowest common denominator of 8 and 9 is 72.