Answer:
G : C : A = 1 : 12 : 4
Step-by-step explanation:
Alex - A
George - G
Carl - C
A = G+12
C = 3A
A + G + C = 68
G : C : A = ?
A = G+12, ---> G = A - 12
C = 3A
A + G + C = 68 ---> A + A - 12 + 3A = 68 ---> 5A = 80 ---> A = 16
G = A - 12, G = 16 - 12 = 4, G = 4
C = 3A = 3*16 = 48, C = 48
G : C : A = 4 : 48 : 16 = 1 : 12 : 4
