3. Решите уравнение: 1) 8/9 * x = 2/9; 2) 5/9 * x = 1; 3) 4/7 * x = 16; 4) 5x = 4/5; 5) x : 9/16 = 32/45; 6) 25/42 : x = 5/6.

1) x = (2/9) / (8/9) = 2/8 = 1/4.
2) x = 1 / (5/9) = 9/5.
3) x = 16 / (4/7) = 16 * 7/4 = 4 * 7 = 28.
4) x = (4/5) / 5 = 4/25.
5) x = (9/16) * (32/45) = (9*32)/(16*45) = (1*2)/(1*5) = 2/5.
6) x = (25/42) / (5/6) = (25/42) * (6/5) = (25*6)/(42*5) = (5*1)/(7*1) = 5/7.