Greatest Common Divisor (GCD) of 121 and 159
The greatest common divisor (GCD) of 121 and 159 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 121 and 159?
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 | 121 ÷ 159 = 0 remainder 121 |
| 2 | 159 ÷ 121 = 1 remainder 38 |
| 3 | 121 ÷ 38 = 3 remainder 7 |
| 4 | 38 ÷ 7 = 5 remainder 3 |
| 5 | 7 ÷ 3 = 2 remainder 1 |
| 6 | 3 ÷ 1 = 3 remainder 0 |
Examples of GCD Calculations
| Numbers | GCD |
|---|---|
| 78 and 18 | 6 |
| 161 and 128 | 1 |
| 101 and 166 | 1 |
| 135 and 56 | 1 |
| 67 and 55 | 1 |