Выполните умножение: 9.3/5*1.10/21 и 1.5/7*5.1/4

1. 9 3/5 * 1 10/21 = 48/5 * 31/21 = (48 * 31) / (5 * 21) = 1488/105 сократим на 3 = 496/35 = 14 6/35.

9 3/5 = (9 * 5 + 3) / 5 = 48/5.

1 10/21 = (1 * 21 + 10) / 21 = 31/21.

2. 1 5/7 * 5 1/4 = 12/7 * 21/4 = (12 * 21) / (7 * 4) = 252/28 = 9.

1 5/7 = (1 * 7 + 5) / 7 = 12/7.

5 1/4 = (5 * 4 + 1) / 4 = 21/4.