Question

daca media aritmetica ponderata a numerelor : 4; 6 si x cu ponderile x+4 ; 3 si 8 este 10. Aflati x.

Answer 1

M.p.=[4·(x+4)+6·3+x·8)]/(x+4+3+8)=10
(4x+16+18+8x)/(x+15)=10
12x+34=10x+150
2x=116
x=58

Answer 2

mp=4(x+4)+6·3+8x /x+4+3+8 =10
4x+16+18+8x /x+15 =10
12x+34=10(x+15)
12x+34=10x+150
12x-10x=150-34
2x=116
x=58