70 = 2 * 5 * 7
60 = 2 * 2 * 3 * 5
80 = 2 * 2 * 2 * 2 * 5
НОК (70; 60; 80) = 2 * 2 * 2 * 2 * 3 * 5 * 7 = 1680
70 = 2 * 5 * 7
60 = 2 * 2 * 3 * 5
80 = 2 * 2 * 2 * 2 * 5
НОК (70; 60; 80) = 2 * 2 * 2 * 2 * 3 * 5 * 7 = 1680