Question

a=(1+2+3+......+50)-(1+2+3+.....+30)

Answer 1

Aflam prima paranteza:
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37+38+39+40+41+42+43+44+45+46+47+48+49+50=1275
Aflam cea de-a doua paranteza:
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30=465
Acum scadem din prima paranteza pe a doua:
1275-465=810
A=810