сроочно, файл прикрплен

Ответ:

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1) 1/25 + 27/75 = 1/25 + 9/25 = 10/25 = 2/5

2) 21/35 - 1/5 = 3/5 - 1/5 = 2/5

3) 27/33 + 14/22 - 16/44 = 9/11 + 7/11 - 4/11 = 12/11 = 1 1/11

4) 16/60 + 36/90 + 81/135 = 4/15 + 6/15 + 9/15 = 19/15 = 1 4/15

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