Сократите дробь (681-683). 7*3/3*14 10*9/30*9 4*12/5*9 14*15/21*20

Сократим дроби:

1) (7 * 3) / (3 * 14);

Сократим дробь на 3.

(7 * 3) / (3 * 14) = (7 * 1) / (1 * 14) = 7/14 = 7 / (7 * 2) = 1 / (1 * 2) = 1/2;

2) (10 * 9) / (30 * 9) = (10 * 9) / (10 * 9 * 3) = (1 * 1) / (1 * 1 * 3) = 1/3;

3) (4 * 12) / (5 * 9) = (4 * 4 * 3) / (5 * 3 * 3) = (4 * 4) / (5 * 3) = 16/15;

4) (14 * 15) / (21 * 20) = 14/20 * 15/21 = (2 * 7) / (2 * 10) * (3 * 5) / (3 * 7) = 7/10 * 5/7 = 1/10 * 5/1 = 5/10 = 5 / (5 * 2) = 1/2.