Is this percent change question right?

Question

I created this question and I'm wondering whether the "same percent change" is right. Chocolate has a 40% increase and vanilla has a 40% decrease. Is it right to say they have the same percent change even if one is increase and the other is decrease?

Here's the question:

The table below shows the number of ice cream flavors sold from June to October. Which flavors have the same percent change between June and September?

a. Cookies and Cream and Vanilla

b. Strawberry and Chocolate

c. Chocolate and Vanilla

d. Vanilla, Cookies and Cream, and Strawberry

Answer 1

Chocolate has a $4\%$ increase, and Vanilla has a $40\%$ decrease.

Now, I assume that was an error of yours, but to answer your question, no. Percent change can be negative.

Percent error in scientific context, though, is always positive.