Learn on PengiEureka Math, Grade 4Chapter 5: Multi-Digit Whole Number Subtraction

Lesson 2: Use place value understanding to decompose to smaller units up to three times using the standard subtraction algorithm, and apply the algorithm to solve word problems using tape diagrams.

In this Grade 4 Eureka Math lesson from Chapter 5, students practice using place value understanding to decompose larger units into smaller units up to three times in order to subtract multi-digit whole numbers using the standard subtraction algorithm. Students work through problems requiring regrouping across the ones, tens, hundreds, and thousands places, such as solving 22,397 minus 3,745 by unbundling thousands and ten thousands. The lesson also applies the algorithm to real-world word problems using tape diagrams to represent the whole, known part, and unknown part.

Section 1

Decomposing Place Value Units

Property

A larger place value unit can be decomposed (unbundled) into 10 of the next smaller place value units without changing the total value of the number. This relationship can be expressed as:
1 of a larger unit=10 of the next smaller unit1 \text{ of a larger unit} = 10 \text{ of the next smaller unit}.
For example: 1 hundred=10 tens1 \text{ hundred} = 10 \text{ tens}, and 1 ten=10 ones1 \text{ ten} = 10 \text{ ones}.

Examples

Section 2

Subtracting Across Zeros

Property

When using the subtraction algorithm, if you need to decompose a unit from a place value that is zero, you must move to the next non-zero digit to the left. Decompose 1 unit from that place, which becomes 10 in the place to its right. Continue this process, changing each intermediate zero to a 9, until you can add 10 to the original place value you needed to regroup for.

Examples

Section 3

Model Subtraction with Tape Diagrams

Property

A tape diagram for subtraction shows a 'whole' amount divided into a 'known part' and an 'unknown part'. To find the unknown part, subtract the known part from the whole.

Whole−Known Part=Unknown PartWhole - Known\ Part = Unknown\ Part

Book overview

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

Continue this chapter

Chapter 5: Multi-Digit Whole Number Subtraction

  1. Lesson 1

    Lesson 1: Use place value understanding to decompose to smaller units once using the standard subtraction algorithm, and apply the algorithm to solve word problems using tape diagrams.

    LearnPractice
  2. Lesson 2Current

    Lesson 2: Use place value understanding to decompose to smaller units up to three times using the standard subtraction algorithm, and apply the algorithm to solve word problems using tape diagrams.

    LearnPractice
  3. Lesson 3

    Lesson 3: Use place value understanding to fluently decompose to smaller units multiple times in any place using the standard subtraction algorithm, and apply the algorithm to solve word problems using tape diagrams.

    LearnPractice
  4. Lesson 4

    Lesson 4: Solve two-step word problems using the standard subtraction algorithm fluently modeled with tape diagrams, and assess the reasonableness of answers using rounding.

    LearnPractice

Lesson overview

Expand to review the lesson summary and core properties.

Expand

Section 1

Decomposing Place Value Units

Property

A larger place value unit can be decomposed (unbundled) into 10 of the next smaller place value units without changing the total value of the number. This relationship can be expressed as:
1 of a larger unit=10 of the next smaller unit1 \text{ of a larger unit} = 10 \text{ of the next smaller unit}.
For example: 1 hundred=10 tens1 \text{ hundred} = 10 \text{ tens}, and 1 ten=10 ones1 \text{ ten} = 10 \text{ ones}.

Examples

Section 2

Subtracting Across Zeros

Property

When using the subtraction algorithm, if you need to decompose a unit from a place value that is zero, you must move to the next non-zero digit to the left. Decompose 1 unit from that place, which becomes 10 in the place to its right. Continue this process, changing each intermediate zero to a 9, until you can add 10 to the original place value you needed to regroup for.

Examples

Section 3

Model Subtraction with Tape Diagrams

Property

A tape diagram for subtraction shows a 'whole' amount divided into a 'known part' and an 'unknown part'. To find the unknown part, subtract the known part from the whole.

Whole−Known Part=Unknown PartWhole - Known\ Part = Unknown\ Part

Book overview

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

Continue this chapter

Chapter 5: Multi-Digit Whole Number Subtraction

  1. Lesson 1

    Lesson 1: Use place value understanding to decompose to smaller units once using the standard subtraction algorithm, and apply the algorithm to solve word problems using tape diagrams.

    LearnPractice
  2. Lesson 2Current

    Lesson 2: Use place value understanding to decompose to smaller units up to three times using the standard subtraction algorithm, and apply the algorithm to solve word problems using tape diagrams.

    LearnPractice
  3. Lesson 3

    Lesson 3: Use place value understanding to fluently decompose to smaller units multiple times in any place using the standard subtraction algorithm, and apply the algorithm to solve word problems using tape diagrams.

    LearnPractice
  4. Lesson 4

    Lesson 4: Solve two-step word problems using the standard subtraction algorithm fluently modeled with tape diagrams, and assess the reasonableness of answers using rounding.

    LearnPractice