Question

Buna! Am nevoie de ajutor la un exercitiu. Suna cam asa :
3x+6x+9x+...+ 300x= 151500.
Stiu ca era o formula dar nu am gasit-o pe nicaieri, daca puteti rezolva pas cu pas, multumesc.

Answer 1

3x+6x+9x+...........+300x=151500

3x*(1+2+3+....+100)=151500

3x*100*101/2=151500

3*50*101x=151500

x=151500/(101*3*50)

x=151500/15150

x=10

Answer 2

3x(1+2+3+...+100)= 3x*100*101:2=3x*50*101=151500
101*50x = 50500
101x=1010
x=10