Answer:
FG = 3 units , GH = 9 units
Step-by-step explanation:
FG : GH = 1 : 3
FH = 12
FG + GH = 1 + 3 = 4 which is also equal to 12
So FG is 1/4 × 12 = 3 units
GH is 3/4 × 12 = 9 units