The large rectangle was reduced to create the small rectangle.What is the missing measure on the small rectangle?

Answer:
x = 4 in
Step-by-step explanation:
scale factor of reduction is
[tex]\frac{6}{18}[/tex] = [tex]\frac{1}{3}[/tex], thus
x = [tex]\frac{1}{3}[/tex] × 12 = 4