Question 364627
{{{(N+3)/(6+N+3)=5/7}}}
{{{(N+3)/(N+9)=5/7}}}
{{{7(N+3)=5(N+9)}}}
{{{7N+21=5N+45}}}
{{{2N=24}}}
{{{N=12}}}
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{{{N/(6+N)=12/18=2/3}}}