Learn on PengienVision, Mathematics, Grade 5Chapter 1: Understand Place Value

Lesson 3: Decimals to Thousandths

In this Grade 5 lesson from enVision Mathematics Chapter 1, students learn to read and write decimals to the thousandths place by connecting fractions with denominators of 1,000 to their decimal equivalents using place-value charts. Students practice converting between forms such as 4/1,000 and 0.004, and explore how the value of a digit changes by a factor of 10 across the tenths, hundredths, and thousandths places.

Section 1

Writing Fractions as Thousandths Decimals

Property

A fraction with a denominator of 1,0001,000 is equivalent to a decimal that extends to the thousandths place, which is the third position to the right of the decimal point.

11000=0.001\frac{1}{1000} = 0.001

Examples

  • The fraction 41000\frac{4}{1000} is read as "four thousandths" and is written as the decimal 0.0040.004.
  • The fraction 971000\frac{97}{1000} is read as "ninety-seven thousandths" and is written as the decimal 0.0970.097.

Section 2

Converting Fractions to Decimals

Property

To convert a fraction with a denominator of 10, 100, or 1,000 to a decimal, write the numerator so its last digit is in the place value indicated by the denominator. The tenths place is one position after the decimal, hundredths is two, and thousandths is three.

Examples

Section 3

Converting Terminating Decimals to Fractions

Property

To convert a terminating decimal to a fraction, write the digits of the decimal in the numerator. The denominator is a power of 10 with the same number of zeros as there are decimal places. Then, simplify the fraction to its lowest terms.

Examples

  • Convert 0.5 to a fraction:
0.5=510=120.5 = \frac{5}{10} = \frac{1}{2}
  • Convert 0.75 to a fraction:
0.75=75100=340.75 = \frac{75}{100} = \frac{3}{4}
  • Convert 0.125 to a fraction:
0.125=1251000=180.125 = \frac{125}{1000} = \frac{1}{8}

Explanation

To change a decimal into a fraction, use its place value to determine the denominator. The number of digits after the decimal point tells you the number of zeros in the denominator (e.g., two places means a denominator of 100). The digits themselves form the numerator. Always remember to simplify the resulting fraction.

Section 4

Decimal Place Value Relationships

Property

The value of a digit in a decimal number is 1010 times the value of the digit to its right and 110\frac{1}{10} the value of the digit to its left.

Examples

  • In the number 0.220.22, the value of the 22 in the tenths place (0.20.2) is 10 times the value of the 22 in the hundredths place (0.020.02).
  • In the number 0.8880.888, the value of the 88 in the hundredths place (0.080.08) is 110\frac{1}{10} the value of the 88 in the tenths place (0.80.8).
  • In 0.0550.055, the value of the 55 in the hundredths place (0.050.05) is 10 times the value of the 55 in the thousandths place (0.0050.005).

Explanation

Our number system is based on powers of ten. As you move from left to right on the place value chart, the value of each position is one-tenth of the value of the position to its left. This means a digit in one place is ten times as great as the same digit in the place to its right. This relationship holds true for both whole numbers and decimals.

Book overview

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Chapter 1: Understand Place Value

  1. Lesson 1

    Lesson 1: Patterns with Exponents and Powers of 10

  2. Lesson 2

    Lesson 2: Understand Whole-Number Place Value

  3. Lesson 3Current

    Lesson 3: Decimals to Thousandths

  4. Lesson 4

    Lesson 4: Understand Decimal Place Value

  5. Lesson 5

    Lesson 5: Compare Decimals

  6. Lesson 6

    Lesson 6: Round Decimals

Lesson overview

Expand to review the lesson summary and core properties.

Expand

Section 1

Writing Fractions as Thousandths Decimals

Property

A fraction with a denominator of 1,0001,000 is equivalent to a decimal that extends to the thousandths place, which is the third position to the right of the decimal point.

11000=0.001\frac{1}{1000} = 0.001

Examples

  • The fraction 41000\frac{4}{1000} is read as "four thousandths" and is written as the decimal 0.0040.004.
  • The fraction 971000\frac{97}{1000} is read as "ninety-seven thousandths" and is written as the decimal 0.0970.097.

Section 2

Converting Fractions to Decimals

Property

To convert a fraction with a denominator of 10, 100, or 1,000 to a decimal, write the numerator so its last digit is in the place value indicated by the denominator. The tenths place is one position after the decimal, hundredths is two, and thousandths is three.

Examples

Section 3

Converting Terminating Decimals to Fractions

Property

To convert a terminating decimal to a fraction, write the digits of the decimal in the numerator. The denominator is a power of 10 with the same number of zeros as there are decimal places. Then, simplify the fraction to its lowest terms.

Examples

  • Convert 0.5 to a fraction:
0.5=510=120.5 = \frac{5}{10} = \frac{1}{2}
  • Convert 0.75 to a fraction:
0.75=75100=340.75 = \frac{75}{100} = \frac{3}{4}
  • Convert 0.125 to a fraction:
0.125=1251000=180.125 = \frac{125}{1000} = \frac{1}{8}

Explanation

To change a decimal into a fraction, use its place value to determine the denominator. The number of digits after the decimal point tells you the number of zeros in the denominator (e.g., two places means a denominator of 100). The digits themselves form the numerator. Always remember to simplify the resulting fraction.

Section 4

Decimal Place Value Relationships

Property

The value of a digit in a decimal number is 1010 times the value of the digit to its right and 110\frac{1}{10} the value of the digit to its left.

Examples

  • In the number 0.220.22, the value of the 22 in the tenths place (0.20.2) is 10 times the value of the 22 in the hundredths place (0.020.02).
  • In the number 0.8880.888, the value of the 88 in the hundredths place (0.080.08) is 110\frac{1}{10} the value of the 88 in the tenths place (0.80.8).
  • In 0.0550.055, the value of the 55 in the hundredths place (0.050.05) is 10 times the value of the 55 in the thousandths place (0.0050.005).

Explanation

Our number system is based on powers of ten. As you move from left to right on the place value chart, the value of each position is one-tenth of the value of the position to its left. This means a digit in one place is ten times as great as the same digit in the place to its right. This relationship holds true for both whole numbers and decimals.

Book overview

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

Continue this chapter

Chapter 1: Understand Place Value

  1. Lesson 1

    Lesson 1: Patterns with Exponents and Powers of 10

  2. Lesson 2

    Lesson 2: Understand Whole-Number Place Value

  3. Lesson 3Current

    Lesson 3: Decimals to Thousandths

  4. Lesson 4

    Lesson 4: Understand Decimal Place Value

  5. Lesson 5

    Lesson 5: Compare Decimals

  6. Lesson 6

    Lesson 6: Round Decimals