Question

cum se rezolva : 1x+2x+3x+4x+5x.........49x+50x=1550

Answer 1

$1x+2x+3x+4x+5x+...+49x+50x=1550\\\\ x(1+2+3+...+49+50)=1550 \\\\ x\cdot \frac{1+50}{2}\cdot 50=1550 \ \ |:50 \\\\ x\cdot \frac{51}{2}=31 \\\\ x\cdot 25,5=31 \\\\ x=31:25,5 \\\\ \boxed{x=1,21}$