Understanding the Relationship Between Addition and Subtraction

This lesson focuses on the relationship between addition and subtraction, exploring how they form fact families. The teacher introduces the concept using numbers 4, 10, and 6, demonstrating how to create related addition and subtraction facts. The lesson covers the commutative property and inverse operations, emphasizing that addition and subtraction are opposites. Students practice solving problems and writing fact families, reinforcing their understanding of these mathematical concepts.

What is the sum of 4 and 6?

• 8

• 9

• 10

• 11

Which of the following is a correct subtraction fact from the numbers 4, 10, and 6?

• 10 - 4 = 5

• 4 - 6 = -2

• 10 - 6 = 4

• 6 - 4 = 2

What is the result of 82 + 68?

• 150

• 140

• 160

• 170

What is the difference when you subtract 68 from 150?

• 82

• 92

• 102

• 72

What is the commutative property of addition?

• Addition is always greater than subtraction

• Addition and subtraction are the same

• Changing the order of numbers changes the sum

• Changing the order of numbers does not change the sum

What is the sum of 365 and 496?

• 881

• 861

• 871

• 751

What is the result of 843 - 484?

• 349

• 359

• 369

• 379

Which of the following is a related addition fact for 843 - 484 = 359?

• 359 + 484 = 843

• 843 + 359 = 484

• 843 + 484 = 359

• 484 + 359 = 843

What should you do when you cannot subtract a smaller digit from a larger one?

• Borrow from the next higher place value

• Add 10 to the smaller digit

• Subtract the larger digit from the smaller one

• Borrow from the next higher place value

• Ignore the subtraction

What is the first step in solving a subtraction problem?

• Start with any number

• Start with the total

• Start with the smaller number

• Start with the middle number