options: Ratios & Proportional Relationships: students learn to recognize, describe, represent, and reason with ratios, rates, proportional relationships, and percent.

Measurement & Data: students learn to work with data and measure attributes such as time, money, length, area, and volume. They may learn to compare measurements to operations and convert between different units of measure.

Statistics & Probability: students learn to analyze and produce data distributions, and build understanding of univariate and bivariate data. They learn to interpret data, make statistical inferences, justify conclusions, understand rules of probability, and use probability to make decisions.

Functions: students learn to define, use, and evaluate functions to model relationships between quantities.

Counting & Cardinality: students learn to know number names and the count sequence, count to tell the number of objects, and compare numbers.

Geometry: students learn to classify geometric figures by their properties, and understand and compare the relationships between them. Students develop and use formulas to compute lengths, areas, and volumes, and they use transformations to generate new shapes and compare existing ones. Geometry can be studied with and without coordinates.

Number & Operations - Fractions: students learn to understand fractions as numbers and may work with them using addition, subtraction, multiplication, and division.

Number Systems and Quantity: students learn to understand the complex number system and reason quantitatively.

Operations & Algebra: students learn to solve problems using algebraic thinking and operations such as addition, subtraction, multiplication, and division. They may learn to identify and explain arithmetic patterns, evaluate or manipulate numerical expressions, and reason with equations and inequalities.

Number & Operations in Base Ten: students learn to work with the base-ten system and build place value understanding.

Modeling: students learn to choose and use appropriate mathematics and statistics to analyze real-world empirical situations, improve decisions, and report on their conclusions and the reasoning behind them.
problem_activity: Narrative
The purpose of this activity is for students to write equivalent expressions in order to find the volume of a figure composed of two right rectangular prisms. Students decompose the figure in two different ways, and write matching expressions to find the volume. For extra support, provide students with colored pencils to shade the two parts of the prism before finding the side lengths they need to calculate the volume.
Monitor and select a student with each of the following strategies to share in the synthesis:
decomposed the figure into a prism with the side lengths 4 ft by 4 ft by 3 ft and a prism with the side lengths 10 ft by 4 ft by 3 ft and wrote this expression (or one written in a different order) to represent the volume:
\((4 \times 4 \times 3) + (10 \times 4 \times 3)\)
decomposed the figure into a prism with the side lengths 4 ft by 8 ft by 3 ft and a prism with the side lengths 6 ft by 4 ft by 3 ft and wrote this expression (or one written in a different order) to represent the volume:
\((4 \times 8 \times 3) + (6 \times 4 \times 3)\)
Action and Expression: Internalize Executive Functions.
Invite students to plan a strategy, including the tools they will use, for finding the volume of the figures. If time allows, invite students to share their plan with a partner before they begin.
Supports accessibility for: Organization, Memory, Attention
Launch
Groups of 2
Activity
10 minutes: individual work time
5 minutes: partner discussion
As students work, consider asking, “Why did you choose to decompose the prism that way?”
Student Facing
Find the volume of the figure by decomposing the figure 2 different ways. Show your thinking. Organize it so it can be followed by others.
[IMG]
[IMG]
For each way you decomposed the figure, write an expression that represents the volume.
Mai used this expression to find the volume of the figure:
\((10 \times 8 \times 3) - (6 \times 4 \times 3)\)
.
Use the diagram to interpret Mai's expression. Show your thinking. Organize it so it can be followed by others.
[IMG]
Student Response
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Activity Synthesis
Ask the two selected students to display their work side by side for all to see.
“How are the diagrams the same? How are they different?”
“How do the expressions relate to the diagrams?”
Display:
\((10 \times 8 \times 3) - (6 \times 4 \times 3)\)
“How does this expression represent the volume of the prism?” (The larger rectangular prism has the side lengths
\(10 \times 8 \times 3\)
cubic feet. We can subtract a rectangular prism with the side lengths
\(6 \times 4 \times 3\)
cubic feet.)
“What is the value of
\((10 \times 8 \times 3) - (6 \times 4 \times 3)\)
?” (168)


correct_option_index: 1

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