Greatest Common Divisor (GCD) of 129 and 57
The greatest common divisor (GCD) of 129 and 57 is 3.
What is the Greatest Common Divisor (GCD)?
The GCD of two integers is the largest positive integer that divides both numbers without leaving a remainder. It is useful in simplifying fractions, finding common factors, and in number theory.
How to Calculate the GCD of 129 and 57?
We use the Euclidean algorithm, which involves the following steps:
- Divide the larger number by the smaller number.
- Replace the larger number with the smaller number and the smaller number with the remainder from the division.
- Repeat this process until the remainder is zero.
- The non-zero remainder just before zero is the GCD.
Step-by-Step Euclidean Algorithm
| Step | Calculation |
|---|---|
| 1 | 129 ÷ 57 = 2 remainder 15 |
| 2 | 57 ÷ 15 = 3 remainder 12 |
| 3 | 15 ÷ 12 = 1 remainder 3 |
| 4 | 12 ÷ 3 = 4 remainder 0 |
Examples of GCD Calculations
| Numbers | GCD |
|---|---|
| 149 and 48 | 1 |
| 87 and 142 | 1 |
| 170 and 13 | 1 |
| 101 and 91 | 1 |
| 150 and 154 | 2 |