Ответ:

Пошаговое объяснение:

x + 3/20 = 5/12 + 2/9

x + 3/20 = 15/36 + 8/36

x + 3/20 = 23/36

x = 23/36 - 3/20

x = 115/180 - 27/180

x = 88/180

x = 22/45

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5/7 - y = 1/54 + 1/9 - 10/27

5/7 - y = 1/54 + 6/54 - 20/54

5/7 - y = -13/54

y = 5/7 + 13/54

y = 270/378 + 91/378

y = 361/378

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3/4 + (5/8 + t) = 11/12 + 7/8

6/8 + 5/8 + t = 22/24 + 21/24

11/8 + t = 43/24

t = 43/24 - 11/8

t = 43/24 - 33/24

t = 10/24

t = 5/12

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(4/5 - k) - 1/3 = 1/6 - 1/10

12/15 - k - 5/15 = 5/30 - 3/30

7/15 - k = 1/15

k = 7/15 - 1/15

k = 6/15

k = 2/5