Answer:
new price= $2.40
Step-by-step explanation:
20%= 20/100= 1/5
$3.00/5= 00.60
1/5 of the price is being subtracted from $3.00
$00.60 is 1/5
3.00-.60= 2.40
Answer

step by step Explanation
The functions given are


We want to find:

This implies that

Let us now simplify

This implies that

Combine the terms to get,

Simple, finding markdown, use these two formulas.
Markdown=Original-New
and
Percent Markdown= Markdown Amount/Original*100
So,
Markdown=612-450
M=162
Markdown%= 162/612*100
M%=0.2647*100
M%=26.5 (rounded)
Thus, there was a 26.5% decrease.