Question 1011472
A boy, m
His brother, n


{{{system(m=n+10,m+4=2(n+4))}}}



{{{m+4=2n+8}}}
{{{m-2n=4}}}
-
{{{n+10-2n=4}}}
{{{-n=4-10}}}
{{{n=6}}}


You find m and figure out the percents.