Ответ:

Пошаговое объяснение:

4)

3 1/6 - x - 1 1/12 = 1/4

3 2/12 - x - 1 1/12 = 3/12

2 1/12 - x = 3/12

x = 2 1/12 - 3/12

x = 1 10/12

x = 1 5/6

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5)

6 5/27 - x + 1 2/9 = 3 20/81

6 5/27 - x + 1 6/27 = 3 20/81

7 11/27 - x = 3 20/81

x = 7 11/27 - 3 20/81

x = 7 33/81 - 3 20/81

x = 4 13/81

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6)

3 5/36 - 1 4/9 + x = 1 17/18

3 5/36 - 1 16/36 + x = 1 17/18

1 25/36 + x = 1 17/18

x = 1 17/18 - 1 25/36

x = 1 34/36 - 1 25/36

x = 9/36

x = 1/4