
Greatest Common Divisor (GCD) of 42 and 193
The greatest common divisor (GCD) of 42 and 193 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 42 and 193?
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 | 42 ÷ 193 = 0 remainder 42 |
2 | 193 ÷ 42 = 4 remainder 25 |
3 | 42 ÷ 25 = 1 remainder 17 |
4 | 25 ÷ 17 = 1 remainder 8 |
5 | 17 ÷ 8 = 2 remainder 1 |
6 | 8 ÷ 1 = 8 remainder 0 |
Examples of GCD Calculations
Numbers | GCD |
---|---|
147 and 141 | 3 |
197 and 85 | 1 |
39 and 85 | 1 |
127 and 121 | 1 |
60 and 172 | 4 |