Learn on PengiEureka Math, Grade 5Chapter 2: Decimal Fractions and Place Value Patterns

Lesson 1: Name decimal fractions in expanded, unit, and word forms by applying place value reasoning.

In this Grade 5 Eureka Math lesson from Chapter 2, students learn to represent decimal fractions such as thousandths and hundredths in standard, expanded, and unit forms using place value reasoning. Students practice writing decimals like 0.001 as fractions, expanded expressions (1 × 1/1000), and word form, building fluency through activities that connect multiplying and dividing decimals by powers of 10. The lesson bridges whole-number place value understanding to decimal notation, preparing students to read and write decimal fractions with precision.

Section 1

Representing Single-Place-Value Decimals

Property

A single digit's value in a decimal can be expressed in various equivalent ways.

Examples

Section 2

Representing Two-Place-Value Decimals

Property

A decimal with digits in two different place values, like 0.0250.025, can be expressed as the sum of its parts.

Examples

The value 25 thousandths can be represented as:

  • Standard Form: 0.0250.025
    • Fraction Form: 251000\frac{25}{1000}
    • Fraction Expanded Form: 2×110+5×110002 \times \frac{1}{10} + 5 \times \frac{1}{1000}
    • Decimal Expanded Form: 0.02+0.005=2×0.01+5×0.0010.02 + 0.005 = 2 \times 0.01 + 5 \times 0.001
    • Word Form: twenty-five thousandths

Section 3

Representing Multi-Digit Decimals in Various Forms

Property

A number's value can be decomposed into the sum of its place value parts and composed back into standard form. These different representations (standard, expanded, unit, and word form) are all equivalent ways to express the same quantity.

Examples

Lesson overview

Expand to review the lesson summary and core properties.

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Section 1

Representing Single-Place-Value Decimals

Property

A single digit's value in a decimal can be expressed in various equivalent ways.

Examples

Section 2

Representing Two-Place-Value Decimals

Property

A decimal with digits in two different place values, like 0.0250.025, can be expressed as the sum of its parts.

Examples

The value 25 thousandths can be represented as:

  • Standard Form: 0.0250.025
    • Fraction Form: 251000\frac{25}{1000}
    • Fraction Expanded Form: 2×110+5×110002 \times \frac{1}{10} + 5 \times \frac{1}{1000}
    • Decimal Expanded Form: 0.02+0.005=2×0.01+5×0.0010.02 + 0.005 = 2 \times 0.01 + 5 \times 0.001
    • Word Form: twenty-five thousandths

Section 3

Representing Multi-Digit Decimals in Various Forms

Property

A number's value can be decomposed into the sum of its place value parts and composed back into standard form. These different representations (standard, expanded, unit, and word form) are all equivalent ways to express the same quantity.

Examples