Learn on PengienVision, Mathematics, Grade 5Chapter 4: Use Models and Strategies to Multiply Decimals

Lesson 8: Use Number Sense to Multiply Decimals

In this Grade 5 enVision Mathematics lesson from Chapter 4, students learn how to use number sense to correctly place the decimal point in the product of a decimal multiplication problem. The lesson teaches students to reason about the relative size of factors — for example, recognizing that multiplying by a decimal less than 1 produces a product smaller than the other factor — and to use place value logic, such as knowing that tenths times tenths yields hundredths. Students apply these strategies to check and correct decimal placement across a variety of multiplication problems involving decimals.

Section 1

How to Multiply Decimal Numbers

Property

How to multiply decimal numbers:
Step 1. Write the numbers in vertical format, lining up the numbers on the right.
Step 2. Multiply the numbers as if they were whole numbers, temporarily ignoring the decimal points.
Step 3. Place the decimal point. The number of decimal places in the product is the sum of the number of decimal places in the factors. If needed, use zeros as placeholders.

Examples

Book overview

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Chapter 4: Use Models and Strategies to Multiply Decimals

  1. Lesson 1

    Lesson 1: Multiply Decimals by Powers of 10

  2. Lesson 2

    Lesson 2: Estimate the Product of a Decimal and a Whole Number

  3. Lesson 3

    Lesson 3: Use Models to Multiply a Decimal and a Whole Number

  4. Lesson 4

    Lesson 4: Multiply a Decimal and a Whole Number

  5. Lesson 5

    Lesson 5: Use Models to Multiply a Decimal and a Decimal

  6. Lesson 6

    Lesson 6: Multiply Decimals Using Partial Products

  7. Lesson 7

    Lesson 7: Use Properties to Multiply Decimals

  8. Lesson 8Current

    Lesson 8: Use Number Sense to Multiply Decimals

Lesson overview

Expand to review the lesson summary and core properties.

Expand

Section 1

How to Multiply Decimal Numbers

Property

How to multiply decimal numbers:
Step 1. Write the numbers in vertical format, lining up the numbers on the right.
Step 2. Multiply the numbers as if they were whole numbers, temporarily ignoring the decimal points.
Step 3. Place the decimal point. The number of decimal places in the product is the sum of the number of decimal places in the factors. If needed, use zeros as placeholders.

Examples

Book overview

Jump across lessons in the current chapter without opening the full course modal.

Continue this chapter

Chapter 4: Use Models and Strategies to Multiply Decimals

  1. Lesson 1

    Lesson 1: Multiply Decimals by Powers of 10

  2. Lesson 2

    Lesson 2: Estimate the Product of a Decimal and a Whole Number

  3. Lesson 3

    Lesson 3: Use Models to Multiply a Decimal and a Whole Number

  4. Lesson 4

    Lesson 4: Multiply a Decimal and a Whole Number

  5. Lesson 5

    Lesson 5: Use Models to Multiply a Decimal and a Decimal

  6. Lesson 6

    Lesson 6: Multiply Decimals Using Partial Products

  7. Lesson 7

    Lesson 7: Use Properties to Multiply Decimals

  8. Lesson 8Current

    Lesson 8: Use Number Sense to Multiply Decimals