Question

calculati media ponderata a numerelor 1 supra 2 ; 1,3(8)si 0,(3)cu ponderile 1,9si ,respectiv,6.

Answer 1

1.3(8)=(138-13)/90=125/90=25/18
0,(3)=3/9=1/3

[1x(1/2)+9x1.3(8)+6x0,(3)]/(1+9+6]=

=[1x(1/2)+9x(25/18)+6x(1/3)]/16=

=(1/2 +25/2 +2)/16=(26/2 +2)/16=(13+2)/16=15/16