# Lesson 18

Modeling Price Information

- Let’s predict some information.

### 18.1: What’ll It Be?

- Use the information to predict the average resale price of the toy on day 12. Explain your reasoning.
- How confident are you in your predictions? Explain your reasoning.

### 18.2: Collectable Toy Price

The graph shows the average resale price for a toy in dollars as a function of time in days.

- Estimate the average rate of change for the first 10 days.
- Estimate the rate of change between days 9 and 10.
- Write a linear function, \(f\), that models the data.
- Predict the price of the toy after 12 days.

### 18.3: More Information

After a few more days, a graph of the average price of the toy looks like this.

- Draw a function (it does not need to be linear) that could model the data.
- Use your graph to predict the average price of the toy after 12 days. How confident are you in this answer?
- Pause here to get additional information from your teacher about the price of the toy. Based on the new information, do you have a new prediction for what happens to the average price of the toy after 12 days? Explain your reasoning.