# Lesson 11

Comparing Groups

### Problem 1

Compare the weights of the backpacks for the students in these three classes.

### Problem 2

A bookstore has marked down the price for all the books in a certain series by 15%.

1. How much is the discount on a book that normally costs \$18.00?
2. After the discount, how much would the book cost?

### Solution

(From Unit 4, Lesson 11.)

### Problem 3

Match each expression in the first list with an equivalent expression from the second list.

### Solution

(From Unit 6, Lesson 22.)

### Problem 4

Angles $$C$$ and $$D$$ are complementary. The ratio of the measure of Angle $$C$$ to the measure of Angle $$D$$ is $$2:3$$. Find the measure of each angle. Explain or show your reasoning.