1)3 4/7 -2 3/5 = 3 20/35 - 2 21/35 = 2 55/35- 2 21/35 = 34/35
2)6 5/6 + 2 3/8 = 6 40/ 48+ 2 18/ 48 = 8 58/ 48 8+1 10/48 = 9 10/48 =9 5/24
4) 9/25*15/7*14/9= 15/5=3
5) (9-40/7) * 21/46 = (9-5 5/7) * 21/46 = (8 2/7) * 21/48 = 58/7*21/48 = 58/16 = 3,625
6)16/5 : 32/15 = 16/5 * 15/32 = 3/2=1,5
7) а)17/3: 1/3 = 17 б) = 19/2 в) 17 - 19/2 = 17-9,5 = 7,5