The GCF of 8 and 36 is 4. The LCM of 8 and 36 is 72.
Factors of 8: 1, 2, 4, 8.
Factors of 36: 1, 2, 3, 4, 6, 9, 12, 18, 36.
Common factors: 1, 2 and 4. The greatest of these is 4.
8 = 2 × 2 × 2
36 = 2 × 2 × 3 × 3
GCF: multiply the prime factors both numbers share: 2 × 2 = 4.
LCM: multiply every prime the maximum number of times it appears in either number: 2 × 2 × 2 × 3 × 3 = 72.
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 4, so GCF(8, 36) = 4.
Multiples of 8: 8, 16, 24, 32, 40, 48, 56, 64, 72, ...
Multiples of 36: 36, 72, 108, ...
The first number in both lists is 72.
4 × 72 = 288 = 8 × 36. This always holds for two numbers, so you can find the LCM as (8 × 36) ÷ 4 = 72.
Divide the top and bottom by the GCF 4: 8/36 = 2/9.
| Numbers | GCF | LCM |
|---|---|---|
| 2 and 8 | 2 | 8 |
| 3 and 8 | 1 | 24 |
| 4 and 8 | 4 | 8 |
| 5 and 8 | 1 | 40 |
| 6 and 8 | 2 | 24 |
| 7 and 8 | 1 | 56 |
| 2 and 36 | 2 | 36 |
| 3 and 36 | 3 | 36 |
| 4 and 36 | 4 | 36 |
| 5 and 36 | 1 | 180 |
| 6 and 36 | 6 | 36 |
| 7 and 36 | 1 | 252 |
See also: factors of 8 · factors of 36.
Different numbers? Use the GCF and LCM calculator (any amount of numbers) or browse all GCF and LCM pairs.