Mathematical Tasks
Buying Soup- 6.RP.3
Domain
Cluster
Ratios and Proportional Relationships
Understand ratio concepts and use ratio reasoning to solve problems.
Standard(s)
6.RP.3 Use ratio and rate reasoning to solve real-world and mathematical problems, e.g.,
by reasoning about tables of equivalent ratios, tape diagrams, double number line
diagrams, or equations.
6.RP.3b Solve unit rate problems including those involving unit pricing and constant
speed. For example, if it took 7 hours to mow 4 lawns, then at that rate, how many
lawns could be mowed in 35 hours? At what rate were lawns being mowed?
6.RP.2 Understand the concept of a unit rate a/b associated with a ratio a:b with b ≠ 0, and
use rate language in the context of a ratio relationship. For example, “This recipe has a
ratio of 3 cups of flour to 4 cups of sugar, so there is 3/4 cup of flour for each cup of
sugar.” “We paid $75 for 15 hamburgers, which is a rate of $5 per hamburger.”
Materials
Task
Activity sheet
Buying Soup
At the grocery store 8 cans of tomato soup cost $6.72.
6 cans of chicken noodle soup cost $5.10.
5 cans of clam chowder soup cost $4.45.
Part 1:
For each type of soup find the unit price for 1 can of soup.
Part 2:
The unit price for Minestrone soup is more than 2 of the types of soup listed above. It is
sold in packs of 8 cans. What is the smallest price possible for a pack of Minestrone soup?
What is the largest price possible for a pack of Minestrone soup?
Part 3:
Write a sentence to explain how you found the answers to Part 2.
Mathematical Tasks
Sixth Grade
Mathematical Tasks

1.
2.
3.
4.
5.
6.
7.
8.
Level I
Student uses inappropriate
solution strategy and does not
get the correct answer.
Rubric
Level II
Not Yet Proficient
 There are one or
two errors.
Level III
Proficient in Performance
 Accurately solves problem
 Part 1: Tomato soup- $0.84 per can;
Chicken noodle soup- $0.85 per can; Clam
Chowder soup- $0.89 per can;
 Part 2: Minestrone could cost as low as
$0.86 per can or as high as $0.88 per can.
Since the cans can only be sold in packs of
8, a pack could cost between $6.88 and
$7.04.
 Part 3: The sentence clearly and accurately
describes their strategy for Part 2.
Standards for Mathematical Practice
Makes sense and perseveres in solving problems.
Reasons abstractly and quantitatively.
Constructs viable arguments and critiques the reasoning of others.
Models with mathematics.
Uses appropriate tools strategically.
Attends to precision.
Looks for and makes use of structure.
Looks for and expresses regularity in repeated reasoning.
Mathematical Tasks
Sixth Grade
Mathematical Tasks
Buying Soup
At the grocery store 8 cans of tomato soup cost $6.72.
6 cans of chicken noodle soup cost $5.10.
5 cans of clam chowder soup cost $4.45.
Part 1:
For each type of soup find the unit price for 1 can of soup.
Part 2:
The unit price for Minestrone soup is more than 2 of the types of soup listed above. It is sold in packs of 8 cans.
What is the smallest price possible for a pack of Minestrone soup? What is the largest price possible for a pack
of Minestrone soup?
Part 3:
Write a sentence to explain how you found the answers to Part 2.
Mathematical Tasks
Sixth Grade