Learn on PengiPengi Math (Grade 4)Chapter 8: Decimals & Fraction Connections

Lesson 3: Comparing and Ordering Decimals

In this Grade 4 lesson from Pengi Math Chapter 8, students learn to compare and order decimals to the hundredths place using inequality symbols (<, >, =). They use area models and number lines as visual tools to justify comparisons, and practice converting between fractions and decimals to compare numbers in different forms. Students also arrange sets of decimals from least to greatest and greatest to least.

Section 1

Recording Decimal Comparisons

Property

To record the result of a comparison between two numbers, aa and bb, we use the following symbols:

  • a<ba < b means "aa is less than bb".
  • a>ba > b means "aa is greater than bb".
  • a=ba = b means "aa is equal to bb".

Examples

Section 2

Compare Decimals Using Area Models

Property

To compare decimals using an area model, represent each decimal by shading a portion of identical wholes (e.g., 10x10 grids). The decimal corresponding to the larger shaded area is the greater number.

Examples

Section 3

Compare Decimals Using Like Units

Property

To compare decimals, rewrite them so they have the same number of decimal places (like units) by adding trailing zeros. This does not change the decimal's value. Once in like units, compare the numbers as if they were whole numbers.

Examples

Section 4

Ordering Decimals

Property

To order a set of decimal numbers, systematically compare pairs of numbers place value by place value, from left to right (ones, then tenths, then hundredths), to determine the position of each number in the sequence.

Examples

Book overview

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Chapter 8: Decimals & Fraction Connections

  1. Lesson 1

    Lesson 1: Understanding Tenths and Hundredths

  2. Lesson 2

    Lesson 2: Reading, Writing, and Modeling Decimals

  3. Lesson 3Current

    Lesson 3: Comparing and Ordering Decimals

  4. Lesson 4

    Lesson 4: Adding Fractions with Tenths and Hundredths

  5. Lesson 5

    Lesson 5: Application: Money and Measurement

Lesson overview

Expand to review the lesson summary and core properties.

Expand

Section 1

Recording Decimal Comparisons

Property

To record the result of a comparison between two numbers, aa and bb, we use the following symbols:

  • a<ba < b means "aa is less than bb".
  • a>ba > b means "aa is greater than bb".
  • a=ba = b means "aa is equal to bb".

Examples

Section 2

Compare Decimals Using Area Models

Property

To compare decimals using an area model, represent each decimal by shading a portion of identical wholes (e.g., 10x10 grids). The decimal corresponding to the larger shaded area is the greater number.

Examples

Section 3

Compare Decimals Using Like Units

Property

To compare decimals, rewrite them so they have the same number of decimal places (like units) by adding trailing zeros. This does not change the decimal's value. Once in like units, compare the numbers as if they were whole numbers.

Examples

Section 4

Ordering Decimals

Property

To order a set of decimal numbers, systematically compare pairs of numbers place value by place value, from left to right (ones, then tenths, then hundredths), to determine the position of each number in the sequence.

Examples

Book overview

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

Continue this chapter

Chapter 8: Decimals & Fraction Connections

  1. Lesson 1

    Lesson 1: Understanding Tenths and Hundredths

  2. Lesson 2

    Lesson 2: Reading, Writing, and Modeling Decimals

  3. Lesson 3Current

    Lesson 3: Comparing and Ordering Decimals

  4. Lesson 4

    Lesson 4: Adding Fractions with Tenths and Hundredths

  5. Lesson 5

    Lesson 5: Application: Money and Measurement