Помогите # 1198 1,2,3 пж

Question

Помогите # 1198 1,2,3 пж

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Answer 1

5/9+12/7(14/3-21/8):7/4=5/9+12/7((112-63)/24)4/7=5/9+12/7*49/24*4/7=
=5/9+7/2*4/7=5/9+2=23/9