Question

If x and y are non-negative integers such that $x + 9 = z, y + 1 = z$ and $x + y < z + 5$, then the maximum possible value of $2x + y$ equals

Answer 1

Given $x+9=z=y+1$ and $x+y<z+5$

$⇒ (z-9)+(z-1)<z+5$

$⇒ z<15$

Hence the maximum value of $z=14$, max of $x=5$ and max of $y=13$

Required answer, $2x+y=2×5+13=23$