Lesson 12 Decompose to Subtract
Let’s subtract within 1,000.
Warm-up What Do You Know About …?
What do you know about 354?
How could we represent the number 354?
Activity 1 Subtract from 354
Find the value of each expression in any way that makes sense to you. Explain or show your reasoning.
Activity 2 Decompose With Base-ten Blocks
Work with your partner to find the value of each expression.
Partner A: Read the expression and represent the larger number using blocks.
Partner B: Decide if you will decompose a ten and explain. Then subtract.
Discuss and write the difference.
Switch roles.
Practice Problem
Problem 1
Find the value of each difference.
Jada drew this picture to find the value of a difference. What difference did Jada calculate? Explain how you know.