Question

Daca a=0,004·10³·1/2-3/2 si b=[2,5+0,1(6)+0,(3)]·(1-1/3)², calculati media ponderata a numerelor a si b stiind ca ponderea lui a este 6, iar ponderea lui b este 3.

Answer 1

a=0,004·10³·1/2-3/2=4·1/2-3/2=2-3/2=(4-3)/2=1/2
b=[2,5+0,1(6)+0,(3)]·(1-1/3)²=[5/2+1/6+1/3]·(2/3)²=[5/2+1/2]·(2/3)²=3·4/9=4/3
2,5=25/10=5/2
0,1(6)=(16-1)/90=15/90=1/6
0,(3)=3/9=1/3

media ponderata=(6x1/2+3*4/3)/(6+3)=(3+4)/9=7/9