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Theory

Cross out common factors

If the numerator and denominator in a fraction contain common factors, they can be crossed out. This is equivalent to dividing both numerator and denominator by the same number.

\frac{2 \cdot 3 \cdot 4}{5 \cdot 3 \cdot 4} = \frac{2 \cdot 3 \cdot 4}{5 \cdot 3 \cdot 4}

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