Answer:
25% decrease
Step-by-step explanation:
The percentage decrease is the change in quantity divided by the original quantity with which we are comparing it to.
We can use a formula shown below:
Percentage Decrease = [tex]\frac{New-Old}{Old}[/tex] * 100
Where
New is the newest value (9)
Old is the previous value (12)
So, substituting, we get:
[tex]\frac{9-12}{12}=-\frac{3}{12}=-\frac{1}{4}*100=-25[/tex]
So the percentage decrease is 25% decrease (or simply -25%)