Question

(12.5/13 + y) - 9.9/13) = 7.7/13.

Answer 1

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Answer 2

(12 5/13 + y) - 9 9/13) = 7 7/13          

12 5/13 + у - 9 9/13 = 7 7/13

у = 7 7/13 + 9 9/13 - 12 5/13

у = 16 16/13 - 12 5/13

у = 4 11/13

 

Проверка:

(12 5/13 + 4 11/13) - 9 9/13) = 16 16/13 - 9 9/13 = 7 7/13