Question

La o lucrare de control o sesime din elevi au obtinut nota 6 , o doime nota 8 si o treime nota 9 . media clase a fost ...

Answer 1

x/6⇒nota 6;
x/2⇒nota 8;
x/3⇒nota 9;
⇒[x/6+x/2+x/3]/3
⇒[x/6+3x/6+2x/6]/3
⇒[6x/6]/3
⇒x/3=[6+8+9]/3=23/3=7,[6]≈8⇒media clasei;