Greatest Common Divisor (GCD) of 189 and 109
The greatest common divisor (GCD) of 189 and 109 is 1.
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 189 and 109?
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 | 189 ÷ 109 = 1 remainder 80 |
| 2 | 109 ÷ 80 = 1 remainder 29 |
| 3 | 80 ÷ 29 = 2 remainder 22 |
| 4 | 29 ÷ 22 = 1 remainder 7 |
| 5 | 22 ÷ 7 = 3 remainder 1 |
| 6 | 7 ÷ 1 = 7 remainder 0 |
Examples of GCD Calculations
| Numbers | GCD |
|---|---|
| 165 and 135 | 15 |
| 141 and 97 | 1 |
| 188 and 137 | 1 |
| 103 and 143 | 1 |
| 165 and 167 | 1 |