Lin’s work for finding the value of is shown.
1
What error do you see in Lin's work?
What error do you see in Lin's work?
1
What would you tell or show Lin so she can revise her work?
What would you tell or show Lin so she can revise her work?
Grade 3 Unit 3
Lesson 9: Subtraction Algorithms (Part 2)
CC BY 2021 Illustrative Mathematics®
Grade 3 Unit 3
Lesson 9: Subtraction Algorithms (Part 2)
CC BY 2021 Illustrative Mathematics®
Decide if each statement is true or false. Be prepared to explain your reasoning.
4 x 5 = 5 x 4
Explain your reasoning.
Lin’s work for finding the value of is shown.
What error do you see in Lin's work?
What would you tell or show Lin so she can revise her work?
Here is a subtraction algorithm you saw in an earlier lesson:
Try using this algorithm to find the value of each difference. Show your reasoning. Organize it so it can be followed by others.
283 - 159
425 - 192
639 - 465
Andre found the value of 739 - 255. His work is shown.
Explain how he subtracted and the value he found for 739 - 255.
125 + 200 = 200 + 125
Explain your reasoning.
300 - 100 = 100 - 300
Explain your reasoning.
591 - 128
832 - 575
