Euclidean Algorithm/Examples/361 and 1178

Examples of Use of Euclidean Algorithm

The GCD of $361$ and $1178$ is:

$\gcd \set {361, 1178} = 19$


Proof

\(\text {(1)}: \quad\) \(\ds 1178\) \(=\) \(\ds 3 \times 361 + 95\)
\(\text {(2)}: \quad\) \(\ds 361\) \(=\) \(\ds 3 \times 95 + 76\)
\(\text {(3)}: \quad\) \(\ds 95\) \(=\) \(\ds 1 \times 76 + 19\)
\(\text {(4)}: \quad\) \(\ds 76\) \(=\) \(\ds 4 \times 19\)

Thus:

$\gcd \set {361, 1178} = 19$

$\blacksquare$


Sources

  • 1971: George E. Andrews: Number Theory ... (previous) ... (next): $\text {2-2}$ Divisibility: Exercise $1 \ \text{(b)}$