Question 1128529
W, number of years of his working life.


{{{W/4+W/5+W/3+13=W}}}


Solve for W, and then compute 15+W.


{{{W-W/4-W/5-W/3=13}}}

{{{60W-15W-12W-20W=13*60}}}

{{{13W=13*60}}}

{{{W=60}}}


{{{60+15=highlight(75)}}}