Question

va roggg
Sunt la scoala si am nevoie de ajutorrr

Answer 1

x/1/3=k⇒x=k/3
y/1/8=k ⇒y=k/8
z/y=7/9 ⇒z=7y/9 ⇒z=7k/8·9⇒z=7k/72
2x+3y-5z=2,75
Inlocuim:
2k/3+3k/8-35k/72=2,75
24·2k/72+9·3k/72-35k/72=2,75
48k+27k-35k=2,75·72
40k=2,75·72
5k=2,75·9
k=0,55·9
x=k/3=0,55·3=1,65
y=k/8=0,55·9/8=0,61875
z=7k/72=7·0,55·9/72=7·0,55/8=0,48125
Media aritmetica:
Ma=(x+y+z)/3
Ma=(1,65+0,61875+0,48125)/3
Ma=2,75/3
Ma=0,91(6)