A focused Grade 3 learning session for Area via Multiplication and Addition using visual models, worked examples, strategy guidance, and a short mastery check.
Student goal: I can use multiplication and addition to find area.
Area via Multiplication and Addition means measuring how much flat space a figure covers by using equal-sized square units.
Question: What is the area of the rectangle?
Why it works: The diagram shows length \(4\) and width \(3\). Area \(= 4 \times 3 = 12\) square units. You can also add: \(3 + 3 + 3 + 3 = 12\) (four rows of three).
Answer: \(12\) sq units
Question: Count the unit squares in the grid. What is the area?
Answer: \(24\) sq cm
Question: The rectangle has \(7\) rows of \(3\) unit squares. Using repeated addition, find the area: \(3 + 3 + 3 + 3 + 3 + 3 + 3 =\) ?
Answer: \(21\) sq units
Question: A rectangle has area \(20\) square feet. Its length is \(5\) feet. What is its width?
Why it works: Area \(= \text{length} \times \text{width}\). So \(20 = 5 \times \text{width}\). Width \(= 20 \div 5 = 4\) feet.
Answer: \(4\) feet
Area via Multiplication and Addition becomes easier when students connect the question to a model, use clear steps, and explain why the answer fits.
Area means every square unit inside the figure.
Use scratch paper. The explanation matters more than simply seeing whether the choice is correct.
A rectangle has length \(6\) units and width \(3\) units. What is its area?
Answer C: \(18\) sq units
Area \(= 6 \times 3 = 18\) square units. You can also count by adding: \(3 + 3 + 3 + 3 + 3 + 3 = 18\) (six rows of three units each).
A square has side length \(4\) cm. What is the area of the square?
Answer C: \(16\) sq cm
A square is a rectangle with equal sides. Area \(= 4 \times 4 = 16\) square cm.
Which rectangle has an area of \(12\) square units?
Answer A: length \(2\), width \(6\)
Choice A: \(2 \times 6 = 12\) ✓. Choice B: \(3 \times 5 = 15\). Choice C: \(4 \times 4 = 16\). Choice D: \(2 \times 5 = 10\).
A rectangle has a length of \(5\) meters and a width of \(2\) meters. Find the area.
Answer B: \(10\) sq meters
Area \(= 5 \times 2 = 10\) square meters. This is \(5\) rows of \(2\) unit squares (or \(2 + 2 + 2 + 2 + 2 = 10\)).
What is the area of the rectangle?
Answer B: \(12\) sq units
The diagram shows length \(4\) and width \(3\). Area \(= 4 \times 3 = 12\) square units. You can also add: \(3 + 3 + 3 + 3 = 12\) (four rows of three).
A rectangle has area \(20\) square feet. Its length is \(5\) feet. What is its width?
Answer B: \(4\) feet
Area \(= \text{length} \times \text{width}\). So \(20 = 5 \times \text{width}\). Width \(= 20 \div 5 = 4\) feet.
How many unit squares fit in this rectangle?
Answer D: \(10\) units
The grid shows 5 columns and 2 rows. Area \(= 5 \times 2 = 10\) square units. You can also count: \(5 + 5 = 10\) (two rows of five).
A rectangle has length \(4\) units and width \(3\) units. There are \(4\) rows with \(3\) unit squares in each row. Find the area by adding: \(3 + 3 + 3 + 3 =\) ?
Answer C: \(12\) sq units
Adding the width \(3\) four times: \(3 + 3 + 3 + 3 = 12\). This is the same as \(4 \times 3 = 12\) square units.
A rectangle has length \(6\) units and width \(2\) units. It has \(6\) rows with \(2\) unit squares in each row. Using repeated addition: \(2 + 2 + 2 + 2 + 2 + 2 =\) ?
Answer B: \(12\) sq units
Adding the width \(2\) six times: \(2 + 2 + 2 + 2 + 2 + 2 = 12\). This is the same as \(6 \times 2 = 12\) square units.
Count the unit squares in the grid. What is the area?
Answer C: \(24\) sq cm
The grid has 6 columns and 4 rows. Area \(= 6 \times 4 = 24\) square cm. You can also count: \(6 + 6 + 6 + 6 = 24\) (four rows of six).
A rectangular garden has length \(8\) feet and width \(3\) feet. What is its area in square feet?
Answer A: \(24\) sq ft
Area \(= 8 \times 3 = 24\) square feet.
