Question 990968
{{{A+B+C=210}}}
,
,
,
{{{A=3C}}}
,
,
,
{{{B=15+C}}}
,
,
,
Substituting,
{{{3C+(15+C)+C=210}}}
{{{5C+15=210}}}
{{{5C=195}}}
{{{C=39}}}
So then,
{{{A=3(39)=117}}}
and
{{{B=15+39=54}}}