Greatest Common Divisor (GCD) of 191 and 120
The greatest common divisor (GCD) of 191 and 120 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 191 and 120?
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 | 191 ÷ 120 = 1 remainder 71 |
| 2 | 120 ÷ 71 = 1 remainder 49 |
| 3 | 71 ÷ 49 = 1 remainder 22 |
| 4 | 49 ÷ 22 = 2 remainder 5 |
| 5 | 22 ÷ 5 = 4 remainder 2 |
| 6 | 5 ÷ 2 = 2 remainder 1 |
| 7 | 2 ÷ 1 = 2 remainder 0 |
Examples of GCD Calculations
| Numbers | GCD |
|---|---|
| 145 and 66 | 1 |
| 161 and 143 | 1 |
| 55 and 105 | 5 |
| 199 and 197 | 1 |
| 124 and 181 | 1 |