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Arithmetic/Multiplying Fractions
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Multiplying fractions
To multiply two fractions:
multiply the numerators to get the new numerator, and
multiply the denominators to get the new denominator.
For instance,
.
Dividing fractions
To divide one fraction by another one, flip numerator and denominator of the second one, and then multiply the two fractions. The flipped-over fraction is called the multiplicative inverse or reciprocal.
For instance,
.
To simplify a compound fraction, like , just remember that a fraction is the same as division, and divide (3/5) ÷ (1/4), which comes to 12/5.