The GCF of 6 and 8 is 2. The LCM of 6 and 8 is 24.
Factors of 6: 1, 2, 3, 6.
Factors of 8: 1, 2, 4, 8.
Common factors: 1 and 2. The greatest of these is 2.
6 = 2 × 3
8 = 2 × 2 × 2
GCF: multiply the prime factors both numbers share: 2 = 2.
LCM: multiply every prime the maximum number of times it appears in either number: 2 × 2 × 2 × 3 = 24.
Divide the larger number by the smaller and repeat with the remainder until it is 0. The last non-zero remainder is the GCF.
The last non-zero remainder is 2, so GCF(6, 8) = 2.
Multiples of 6: 6, 12, 18, 24, 30, ...
Multiples of 8: 8, 16, 24, 32, ...
The first number in both lists is 24.
2 × 24 = 48 = 6 × 8. This always holds for two numbers, so you can find the LCM as (6 × 8) ÷ 2 = 24.
Divide the top and bottom by the GCF 2: 6/8 = 3/4.
| Numbers | GCF | LCM |
|---|---|---|
| 2 and 6 | 2 | 6 |
| 3 and 6 | 3 | 6 |
| 4 and 6 | 2 | 12 |
| 5 and 6 | 1 | 30 |
| 6 and 7 | 1 | 42 |
| 6 and 9 | 3 | 18 |
| 2 and 8 | 2 | 8 |
| 3 and 8 | 1 | 24 |
| 4 and 8 | 4 | 8 |
| 5 and 8 | 1 | 40 |
| 7 and 8 | 1 | 56 |
| 8 and 9 | 1 | 72 |
See also: factors of 6 · factors of 8 · 6/8 as a decimal.
Different numbers? Use the GCF and LCM calculator (any amount of numbers) or browse all GCF and LCM pairs.