Greatest Common Divisor (GCD) of 30 and 55
The greatest common divisor (GCD) of 30 and 55 is 5.
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 30 and 55?
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 | 30 ÷ 55 = 0 remainder 30 |
| 2 | 55 ÷ 30 = 1 remainder 25 |
| 3 | 30 ÷ 25 = 1 remainder 5 |
| 4 | 25 ÷ 5 = 5 remainder 0 |
Examples of GCD Calculations
| Numbers | GCD |
|---|---|
| 131 and 138 | 1 |
| 108 and 176 | 4 |
| 71 and 186 | 1 |
| 154 and 63 | 7 |
| 44 and 126 | 2 |