Understanding Addition and Subtraction

This lesson focuses on adding and subtracting 10 or 100 from a three-digit number using place value. It includes examples with cartons of milk, Madeline's stamp collection, and a cookie problem to reinforce understanding. The lesson emphasizes how changes in the tens and hundreds places affect the overall number.

What is the main focus of this lesson?

• Understanding fractions

• Dividing three-digit numbers

• Adding and subtracting 10 or 100 from a three-digit number

• Multiplying three-digit numbers

If you start with 430 cartons of milk and sell 10, how many cartons are left?

• 430

• 410

• 440

• 420

When you subtract 10 from 430, which place value changes?

• Ones place

• None of the above

• Tens place

• Hundreds place

If you add 10 to 430 cartons of milk, what is the new total?

• 420

• 430

• 440

• 450

When you add 10 to 430, which place value changes?

• Hundreds place

• Tens place

• None of the above

• Ones place

What is 100 less than 430?

• 230

• 430

• 530

• 330

What is 100 more than 430?

• 330

• 530

• 430

• 630

Madeline starts with 671 stamps and gets 10 more. How many stamps does she have now?

• 691

• 671

• 661

• 681

After receiving 100 more stamps, how many stamps does Madeline have?

• 771

• 681

• 671

• 781

Mr. Baum bakes 135 cookies and sells 10. How many cookies are left?

• 115

• 145

• 135

• 125