460

1)1/2 ×1/6 и 2/3 = 1/12 и 2/3 = 1/12 и 8/12

2)1/4 ×5/7 и 9/28 = 5/28 и 9/28

3)1/5 ×11/20 и 3/10 = 11/100 и 3/10 = 11/100 и 30/100

4)3/4 × 7/8 и 3/16 = 21/32 и 3/16 = 21/32 и 6/32