The formula to calculate the percentage change is given as
[tex]\text{Percentage Change = }\frac{Original\text{ Amount}-\text{Final Amount}}{Original\text{ Amount}}\times100[/tex]The question gives us:
Original amount: 25
End amount: 18
Substituting, we have
[tex]\begin{gathered} C=\frac{25-18}{25}\times100 \\ =\frac{7}{25}\times100 \\ =28 \end{gathered}[/tex]The percentage change is a 28% decrease.