Ratio ( model measure to actual measure)=model measure / actual measure
Data:
model width=0.8 m
actual width=20 m
Ratio=0.8 m / 20 m=0.04
ratio= model height / real height ⇒ real height=model height / ratio
Data:
ratio=0.04
model height=1.2 m
Therefore:
real height=1.2 m / 0.04=30 m
Answer: the height is 30 m.
Other method:
model width/actual width=model height / actual height
Data:
model width=0.8 m
actual width=20 m
model height=1.2 m
Therefore:
0.8 m / 20 m=1.2 m / actual height
0.04 =1.2 m/ actual height
actual height=1.2 m / 0.04 =30 m
Answer:the height is 30 m