Question 1169078
If using n for Nelson and c for his Cousin, then following the description literally will give you  {{{system(n+15=(6/7)(c+15),n=(3/4)c)}}}.  Solve the system.


Method to try:  Substitute for n in the first equation.  Multiply both sides by the lowest common denominator of {{{4*7=28}}}, and simplify.  Solve for d, fist and use it to evaluate n.


A few steps of algebra will show you {{{c=20}}} and {{{highlight(n=15)}}}.


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