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

# Key Concepts

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## Key Concepts

• If $$a,b,$$ and $$c$$ are numbers where $$c\ne 0$$, then $$\frac{a}{c}+\frac{b}{c}=\frac{a+c}{c}$$.
• If $$a,b,$$ and $$c$$ are numbers where $$c\ne 0$$, then $$\frac{a}{c}-\frac{b}{c}=\frac{a-c}{c}$$.