Mathematics » Introducing Fractions » Add and Subtract Fractions with Common Denominators

Key Concepts

Key Concepts

  • Fraction Addition
    • If \(a,b,\) and \(c\) are numbers where \(c\ne 0\), then \(\frac{a}{c}+\frac{b}{c}=\frac{a+c}{c}\).
    • To add fractions, add the numerators and place the sum over the common denominator.
  • Fraction Subtraction
    • If \(a,b,\) and \(c\) are numbers where \(c\ne 0\), then \(\frac{a}{c}-\frac{b}{c}=\frac{a-c}{c}\).
    • To subtract fractions, subtract the numerators and place the difference over the common denominator.

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