1260 = 2 * 2 * 3 * 3 * 5 * 7
1980 = 2 * 2 * 3 * 3 * 5 * 11
НОД (1260; 1980) = 2 * 2 * 3 * 3 * 5 = 180
1260/1980 = 7/11
1260 = 2 * 2 * 3 * 3 * 5 * 7
1980 = 2 * 2 * 3 * 3 * 5 * 11
НОД (1260; 1980) = 2 * 2 * 3 * 3 * 5 = 180
1260/1980 = 7/11