I'll help.
[tex] \frac{1}{3}x = 9 \frac{1}{2} [/tex]
[tex]x = ?[/tex]
↓
[tex] \frac{1}{3} x = \frac{19}{2} [/tex]
[tex]x = \frac{57}{2} [/tex]
"How it can be 57 ?"
The number 19 is multiplied by the number 3 at the bottom left.
19 × 3 = 57.