[tex]x-nr. \ de \ elevi \\\\ \frac{1}{2} \ din \ x= \frac{1}{2}*x\to \frac{x}{2}-matematica \\\\ x^{(2}-\frac{x}{2}=\frac{2x-x}{2}\to \frac{x}{2}-restul \\\\ \frac{1}{4} \ din \ x =\frac{1}{4}*x\to\frac{x}{4}-natura \\\\ \frac{x}{2}^{(2}-\frac{x}{4}=\frac{2x-x}{4}\to\frac{x}{4}-noul \ rest \\\\ \frac{1}{7} \ din \ x= \frac{1}{7}*x\to\frac{x}{7}-mediteaza \\\\ \frac{x}{4}^{(7}-\frac{x}{7}^{(4}=\frac{7x-4x}{28}\to\frac{3x}{28}-noul \ nou \ rest \\\\ \frac{3x}{28}=3 \\\\ x=\frac{28*3}{3} \\\\ \boxed{x=28 \ elevi}[/tex]
