Вариант 1.
1. а) 7y - 39 = 717,
7y = 717 + 39,
7y = 756,
y = 756 : 7,
y = 108.
б) x + 3x = 76,
4x = 76,
x = 76 : 4,
x = 19.
2. a) 24a + 16 + 13a = 37a + 16;
б) 25*m*16 = 400m.
3. НОД(12, 18) = 6;
НОК(12, 18) = 36.
Вариант 2.
1. а) 8x + 14 = 870,
8x = 870 - 14,
8x = 856,
x = 856 : 8,
x = 107.
б) 5y - y = 68,
4y = 68,
y = 68 : 4,
y = 17.
2. а)37k + 13 + 22k = 59k + 13;
б) 50*n*12 = 600n.
3. НОД(12, 30) = 6;
НОК(12, 30) = 60.