Lesson · M.2.3

Multiplying and Dividing Fractions

Multiply fractions straight across and divide by flipping the second fraction, with clinical dosage and supply examples worked step by step.

ObjectiveM.2.3Read3 minExam weightFractions ≈ 20% of Mathematics

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What you will be able to do

  • Multiply two fractions, or a fraction and a whole number, and reduce the product.
  • Convert mixed numbers to improper fractions before multiplying or dividing.
  • Divide fractions by inverting the second fraction and multiplying.

What the lesson concludes

  • Multiplying fractions never needs a common denominator: multiply the numerators, multiply the denominators, then reduce.
  • A whole number multiplies as itself over 1.
  • Dividing by a fraction means multiplying by its reciprocal, the fraction flipped upside down.
  • Convert every mixed number to an improper fraction before you multiply or divide, then convert the answer back at the end.
  • Two numbers are reciprocals when their product is 1, which is exactly why flipping and multiplying works for division.