## 237. Math Puzzle $2 / 85$

Karl and Walter are together 109 years old, Walter and Sven together 56 years, and Karl and Sven in total 85 years old.

How old is each?
Karl $=x$; Walter $=y$; Sven $=z$

1.) $x+y=109$; 2.) $y+z=56$; 3.) $x+z=85$

$z=56-y ; z=85-x ; 56-y=85-x ; x-y=29$

Rearranged for $x$ and substituted into equation 1.: $29+2 y=109 ; y=40$.

By substituting $y$ into the other two equations: Karl $=69$; Walter $=40$; Sven $=16$