### Home > A2C > Chapter 7 > Lesson 7.1.1 > Problem 7-15

7-15.

The cost of food has been increasing by 4% per year for many years. To find the cost of an item 15 years ago, Heather said, “*Take the current price and divide it by* (1.04)^{15}.”

Her friend Elissa said, “*No, you should take the current price and multiply it by* (0.96)^{15} *!*”

Explain who is correct and why.

Since the situation describes an increase, the multiplier must be *x* will represent cost.

What will be

Heather is correct, because a