Fishtank Learning
7th Grade Math
Unit 1: Proportional Relationships
Lesson 8
Objective
Compare proportional and non-proportional relationships.
Anchor Problems - Problem 1
Syrus is 12 years old and has a younger sister, Samira, who is 6 years old. Syrus says, “Our ages are in a proportional relationship because I am two times as old as my sister.”
Is Syrus correct? Justify your answer.
Anchor Problems - Problem 2
At the zoo, you can buy tickets to take a train ride between exhibits. Each ticket costs $0.50; however, there is a deal that if you buy 10 or more tickets, you only pay $4.00.
Is the cost of the tickets proportional to the number of tickets you buy? Create a table with some values and plot the points on a coordinate plane.
Anchor Problems - Problem 3
Four tables and four graphs are shown below. Which tables and graphs represent proportional relationships? Explain your reasoning for each one.
Problem Set
Target Task
Two ice cream shops are located across the street from one another on a busy street.
- At Max’s Ice Cream shop, you can buy a sundae with unlimited toppings for $5 per sundae.
- At Mary’s Ice Cream shop, you can buy a sundae by paying $3.50 for the ice cream and then $0.75 for each topping.
At which ice cream shop is the cost of the sundaes (including the toppings), proportional to the number of sundaes purchased? Justify your answer with tables, graphs, or an explanation.