Răspuns :
a+b+c /3 =22.8
12.4+23.8 +c /3 =22.8
36.2+c/3 =22.8
36.2+c =22.8*3
36.2+c =68.4
c =68.4-36.2 =32.2
v ; 12.4+23.8+32.2 /3 =22.8
12.4+23.8 +c /3 =22.8
36.2+c/3 =22.8
36.2+c =22.8*3
36.2+c =68.4
c =68.4-36.2 =32.2
v ; 12.4+23.8+32.2 /3 =22.8