Lesson 7 Compose a Larger Unit
Let’s add three-digit numbers and compose tens or hundreds.
Warm-up How Many Do You See: Are They the Same?
How many do you see? How do you see them?
Activity 1 Compose a Ten or a Hundred
Find the value of each expression. Show your thinking. Use base-ten blocks if it helps.
Compare your thinking with your partner.
Activity 2 Walk About and Add
Problem 1
Directions:
Find a partner and record your numbers to make an expression.
Discuss if you think you would need to compose a ten or a hundred when adding your numbers.
Find the value of the sum. Show your thinking.
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Will you need to compose a ten? Yes or No
Will you need to compose a hundred? Yes or No
Find the value of the sum. Show your thinking.
Problem 2
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Will you need to compose a ten? Yes or No.
Will you need to compose a hundred? Yes or No.
Find the value of the sum. Show your thinking.
Problem 3
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Will you need to compose a ten? Yes or No
Will you need to compose a hundred? Yes or No
Find the value of the sum. Show your thinking.
Practice Problem
Problem 1
Find the value of each sum. Explain your reasoning.