А) 4 1/30 = 4 + 1/30 = 4 + 1/30 = 4 + 1/30 = 4 1/30
3 1/20 = 3 + 1/20 = 3 + 3/60 = 3 + 3/60 = 3 3/60 = 3 1/20

4 1/30 - 3 1/20 = 4 1/30 - 3 1/20 = (4 - 3) + (1/30 - 1/20) = 1 + (2/60 - 3/60) = 1 - (1/60) = 1 - 1/60 = 59/60

Б) 14 1/12 = 14 + 1/12 = 14 + 5/60 = 14 + 5/60 = 14 5/60 = 14 1/12
1 1/18 = 1 + 1/18 = 1 + 3/54 = 1 + 3/54 = 1 + 1/18

14 1/12 - 1 1/18 = 14 1/12 - 1 1/18 = (14 - 1) + (1/12 - 1/18) = 13 + (3/36 - 2/36) = 13 + (1/36) = 13 + 1/36 = 469/36

В) 3 9/34 = 3 + 9/34 = 3 + 27/102 = 3 + 27/102 = 3 + 3/17 = 3 3/17
2 7/17 = 2 + 7/17 = 2 + 4/17 = 2 4/17

3 9/34 - 2 7/17 = 3 9/34 - 2 7/17 = (3 - 2) + (9/34 - 7/17) = 1 + (18/68 - 34/68) = 1 - (16/68) = 1 - 4/17 = 13/17