• Title: Rational Numbers (Addition and Multiplication)

  • Series: Start Learning Numbers

  • Parent Series: Start Learning Mathematics

  • Chapter: Numbers

  • YouTube-Title: Start Learning Numbers 10 | Rational Numbers (Addition and Multiplication)

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  • Quiz Content

    Q1: Use the definition of the multiplication in $\mathbb{Q}$ to calculate the following product. Which is correct?

    A1: $[(4,2)] \cdot [(6,3)] = [(24,6)]$

    A2: $[(4,2)] \cdot [(6,3)] = [(6,6)]$

    A3: $[(4,2)] \cdot [(6,3)] = [(10,8)]$

    A4: $[(4,2)] \cdot [(6,3)] = [(12,12)]$

    A5: $[(4,2)] \cdot [(6,3)] = [(4,2)]$

    Q2: Use the definition of the addition in $\mathbb{Q}$ to calculate the following product. Which is correct?

    A1: $[(4,2)] + [(1,3)] = [(14,6)]$

    A2: $[(4,2)] + [(1,3)] = [(10,5)]$

    A3: $[(4,2)] + [(1,3)] = [(5,5)]$

    A4: $[(4,2)] + [(1,3)] = [(8,3)]$

    A5: $[(4,2)] + [(1,3)] = [(0,1)]$

    Q3: What is not correct?

    A1: $(\mathbb{Q}, \cdot)$ is an abelian group.

    A2: $(\mathbb{Q}, +)$ is an abelian group.

    A3: $\mathbb{Q}$ together with the addition and multiplication is a field.

    A4: $\mathbb{Q}$ together with the addition and multiplication satisfies the common distributive laws.

  • Last update: 2025-07

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