Learn on PengienVision, Mathematics, Grade 7Chapter 1: Integers and Rational Numbers

Lesson 2: Understand Rational Numbers

In this Grade 7 enVision Mathematics lesson from Chapter 1, students learn to recognize rational numbers and convert them from fraction form to decimal form by dividing the numerator by the denominator. The lesson covers the difference between terminating decimals, where the remainder reaches zero, and repeating decimals, where a digit or block of digits repeats infinitely and is written using bar notation. Students practice identifying whether a given decimal is rational based on whether it terminates or repeats.

Section 1

Terminating vs. Repeating Decimals

Property

To convert a rational number a/b (where a and b are integers) to a decimal, divide the numerator by the denominator using long division. The resulting decimal will either be a terminating decimal (if the division eventually results in a remainder of 0) or a repeating decimal (if a non-zero remainder repeats, creating an infinitely repeating sequence of digits in the quotient).

Examples

  • Terminating: To convert 5/8 to a decimal, calculate 5 divided by 8. The division ends with a remainder of 0, resulting in the terminating decimal 0.625.
  • Repeating: To convert 2/11 to a decimal, calculate 2 divided by 11. The remainders 2 and 9 alternate endlessly, resulting in the repeating decimal 0.181818...

Explanation

Think of a fraction as a division problem waiting to be solved. When you perform long division, you are looking at the leftovers (remainders). If you eventually have no leftovers, the decimal stops cleanly. If you start seeing the same leftovers over and over, you are caught in a mathematical loop, which means your decimal will repeat that pattern forever.

Section 2

Identifying Rational Numbers by their Decimal Form

Property

A number is rational if and only if its decimal representation either terminates (ends) or repeats.

Examples

Book overview

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Chapter 1: Integers and Rational Numbers

  1. Lesson 1

    Lesson 1: Relate Integers and Their Opposites

  2. Lesson 2Current

    Lesson 2: Understand Rational Numbers

  3. Lesson 3

    Lesson 3: Add Integers

  4. Lesson 4

    Lesson 4: Subtract Integers

  5. Lesson 5

    Lesson 5: Add and Subtract Rational Numbers

  6. Lesson 6

    Lesson 6: Multiply Integers

  7. Lesson 7

    Lesson 7: Multiply Rational Numbers

  8. Lesson 8

    Lesson 8: Divide Integers

  9. Lesson 9

    Lesson 9: Divide Rational Numbers

  10. Lesson 10

    Lesson 10: Solve Problems with Rational Numbers

Lesson overview

Expand to review the lesson summary and core properties.

Expand

Section 1

Terminating vs. Repeating Decimals

Property

To convert a rational number a/b (where a and b are integers) to a decimal, divide the numerator by the denominator using long division. The resulting decimal will either be a terminating decimal (if the division eventually results in a remainder of 0) or a repeating decimal (if a non-zero remainder repeats, creating an infinitely repeating sequence of digits in the quotient).

Examples

  • Terminating: To convert 5/8 to a decimal, calculate 5 divided by 8. The division ends with a remainder of 0, resulting in the terminating decimal 0.625.
  • Repeating: To convert 2/11 to a decimal, calculate 2 divided by 11. The remainders 2 and 9 alternate endlessly, resulting in the repeating decimal 0.181818...

Explanation

Think of a fraction as a division problem waiting to be solved. When you perform long division, you are looking at the leftovers (remainders). If you eventually have no leftovers, the decimal stops cleanly. If you start seeing the same leftovers over and over, you are caught in a mathematical loop, which means your decimal will repeat that pattern forever.

Section 2

Identifying Rational Numbers by their Decimal Form

Property

A number is rational if and only if its decimal representation either terminates (ends) or repeats.

Examples

Book overview

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

Continue this chapter

Chapter 1: Integers and Rational Numbers

  1. Lesson 1

    Lesson 1: Relate Integers and Their Opposites

  2. Lesson 2Current

    Lesson 2: Understand Rational Numbers

  3. Lesson 3

    Lesson 3: Add Integers

  4. Lesson 4

    Lesson 4: Subtract Integers

  5. Lesson 5

    Lesson 5: Add and Subtract Rational Numbers

  6. Lesson 6

    Lesson 6: Multiply Integers

  7. Lesson 7

    Lesson 7: Multiply Rational Numbers

  8. Lesson 8

    Lesson 8: Divide Integers

  9. Lesson 9

    Lesson 9: Divide Rational Numbers

  10. Lesson 10

    Lesson 10: Solve Problems with Rational Numbers