A. The difference in ACTUAL divided by the difference in BLUEPRINT for each of the values must be equal.
[tex]\dfrac{6-3}{8-4} =\dfrac{12-8}{9-6} =\dfrac{16-12}{12-9} =\dfrac{20-16}{12-12} = \dfrac{24-20}{18-15}[/tex]
B. [tex]\dfrac{Actual}{Blueprint}=\dfrac{3\ ft}{4\ in}\div\dfrac{4}{4}=\dfrac{0.75\ ft}{1\ in}[/tex]
C. y = 0.75x
x = 21 in y = 7 ft
y = 0.75(21) 7 = 0.75x
y = 15.75 ft [tex]\dfrac{7}{0.75}=x[/tex]
[tex]9\dfrac{1}{3}\ in = x[/tex]
