Answer:
20%
Step-by-step explanation:
A pair of jeans cost $45 before the sale.
The sale is taking $9 off of the original price.
Then
$45 - 100%
$9 - x%
Write a proportion:
[tex]\dfrac{45}{9}=\dfrac{100}{x}[/tex]
Cross multiply:
[tex]45\cdot x=9\cdot 100\\ \\45x=900\\ \\x=\dfrac{900}{45}\\ \\x=20\%[/tex]
