Answer:
2 cm
Step-by-step explanation:
First student:
Scale factor = 3 cm to 15 m
Height of original building = 20 m
Height of the first student's model = [tex] \frac{20*3}{15} = \frac{60}{15} = 4 cm [/tex]
Second student:
Scale factor = 4.5 cm to 15 m
Height of original building = 20 m
Height of the first student's model = [tex] \frac{20*4.5}{15} = \frac{90}{15} = 6 cm [/tex]
Difference between the heights of the two students' models = 6 cm - 4 cm = 2cm