Răspuns :
Ma=(a+b+c)/3=600
a+b+c=3x600
a+b+c=1800
(a+b)/2=220
a+b=220x2
a+b=440
440+c=1800
c=1800-440
c=1360
a=1/5 din 1360
a=1360:5
a=272
272+b=440
b=440-272
b=168
a+b+c=3x600
a+b+c=1800
(a+b)/2=220
a+b=220x2
a+b=440
440+c=1800
c=1800-440
c=1360
a=1/5 din 1360
a=1360:5
a=272
272+b=440
b=440-272
b=168
( a+b+c):3=600
a+b+c=600·3
a+b+c=1800
(a+b):2=220
a+b=220·2
a+b=440
440+c=1800
c=1800-440
c=1360
a=1/5 din 1360
a=1360:5
a=272
272+b=440
b=440-272
b=168
Verificare: a+b+c=?
272+168+1360=1800