31/80+(3/16+39/80)= 2/45+(3/45+7/9)= (3/7+5/14)+1/14= 7/15+(2/15+1/5)= 3/16+(1/16+5/8)=...

Question

31/80+(3/16+39/80)=
2/45+(3/45+7/9)=
(3/7+5/14)+1/14=
7/15+(2/15+1/5)=
3/16+(1/16+5/8)=
(1/13+1/14)+12/13=

Answer 1

Вот решение. Надеюсь, понятно

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