Lesson 11

Comparing Groups

Let’s compare two groups.

Problem 1

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

Three dot plots for “backpack weight in pounds” are labeled “seventh grade,” “ninth grade,” and “eleventh grade.” 

 

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?
(From Unit 4, Lesson 11.)

Problem 3

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

A:

\(6(x+2y) - 2(y-2x)\)

B:

\(2.5(2x+4y) - 5(4y-x)\)

C:

\(4(5x-3y) - 10x + 6y\)

D:

\(5.5(x+y) - 2(x+y) + 6.5(x+y)\)

E:

\(7.9(5x+3y) - 4.2(5x +3y) - 1.7(5x +3y)\)

1:

\(10(x-y)\)

2:

\(10(x+y)\)

3:

\(10x+6y\)

4:

\(10x-6y\)

(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.

(From Unit 7, Lesson 2.)