Question 1055653
Let the ages be {{{N-2}}},{{{N}}}, and {{{N+2}}}.
{{{N-2+3(N+2)=5(5N-5)}}}
{{{N-2+3N+6=25N-25}}}
{{{4N+4=25N-25}}}
{{{-21N=-29}}}
{{{N=29/21}}}
However the answer must be an integer.
Check your problem setup especially that last sentence.