So the question is Let $x,y, z$ Be digits so that the $9$-digit number $5x36y98z2$ is divisible by $792$.
$1) ~$ Without calculating $x$ and $y$, explain why $z = 3$ or $ 7$.
$2)~$ Without calculating $x$, show that $y = 0$ or $9$.
$3)~$ Find all combinations of $x, y, z$