# Proportional and Nonproportional Relationships

## Presentation on theme: "Proportional and Nonproportional Relationships"— Presentation transcript:

Proportional and Nonproportional Relationships
7th Grade Math Lesson Objective: Students will identify proportional and nonproportional relationships.

Vocabulary Proportional Nonproportional
Two quantities that have a constant ratio Example: Nonproportional Two quantities that do NOT have a constant ratio 16 = 16 17 ≠ 20

Identifying Proportional Relationships - Tables
Kudzu is a vine that grows an average of 7.5 feet every 5 days. Is the number of days of growth proportional to the length of the vine as measured on the last day? Length 7.5 15 22.5 30 # of Days 5 10 20 Yes

Identifying Proportional Relationships - Tables
The Vista Marina rents boats for \$25 per hour. In addition to the rental fee, there is a \$12 charge for fuel. Is the number of hours you can rent the boat proportional to the total cost? Total Cost 37 62 87 112 Hours 1 2 3 4 No

Identifying Proportional Relationships – Cross Products
Ms. Cochran is planning a year-end pizza party for her students. Ace Pizza offers free delivery and charges \$8 for each medium pizza. Is the cost of an order proportional to the number of pizzas ordered? 16 = 16 Yes

Identifying Proportional Relationships – Cross Products
Uptown Pizzeria sells medium pizzas for \$7 each but charges a \$3 delivery fee per order. Is the cost of an order proportional to the number of pizzas ordered? 17 ≠ 20 No