Question

The figures shown are similar. What is the scale factor? Two similar pentagons, one pentagon with base 9 and one pentagon with base 12.
a. 1 1/3
b. 2/3
c. 1 1/4
d. 3/4

Answer 1

$9:12=\frac{9}{12}=\frac{9:3}{12:3}=\boxed{\frac{3}{4}}\leftarrow\boxed{d.}$

Answer 2

$\sf You \ have \ to \ set \ it \ as \ fraction \ then \ simplify. \\ \\ \frac{9}{12} \\ \\ GCF = 3 \\ \\ Reduce \ by \ dividing \ both \ denominator \ and \ numerator \ by \ 3. \\ \\ \dfrac{9 \div 3}{12 \div 3} \\ \\ = \frac{3}{4}$