Final answer:
To find the final sale price of the security system, calculate the marked-up price by adding Y% of $X to $X, then find Z% of that price for the discount, and subtract this discount from the marked-up price.
Step-by-step explanation:
The question involves a multistep percent change calculation to find the final sale price of a security system that was initially priced at $X, marked up by Y%, and then reduced by Z%. To solve this, one would take the following steps:
Calculate the markup price by finding Y% of $X and adding it to $X.
Determine the discount amount by finding Z% of the new price.
Subtract the discount amount from the marked-up price to get the final sale price.
Here's how the calculations would look:
Markup Price = $X + ($X * (Y/100))
Discount Amount = Markup Price * (Z/100)
Final Sale Price = Markup Price - Discount Amount
Note that to convert a percentage to a decimal, you divide by 100. For example, a 10% sales tax on a $150.00 item calculates as $150.00 x 0.10 = $15.00.