Question 1169239
The original fraction,  {{{n/(n+2)}}}


The description second sentence,  {{{(n+1)/(n+3)=4/5}}}
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{{{4(n+3)=5(n+1)}}}
{{{4n+12=5n+5}}}
{{{7=n}}}



The original fraction  {{{highlight(7/9)}}}