5.3 Multiplying and Dividing Fractions

Unit Goals

  • Students extend multiplication and division of whole numbers to multiply fractions by fractions and divide a whole number and a unit fraction.

Section A Goals

  • Recognize that $\frac{a}{b} \times \frac{c}{d}=\frac{a \ \times \ c}{b \ \times \ d}$ and use this generalization to multiply fractions numerically.
  • Represent and describe multiplication of a fraction by a fraction using area concepts.

Section B Goals

  • Divide a unit fraction by a whole number using whole-number division concepts.
  • Divide a whole number by a unit fraction using whole-number division concepts.

Section C Goals

  • Solve problems involving fraction multiplication and division.
Read More

Glossary Entries

  • area

    The number of square units that cover a flat figure without gaps or overlaps.

  • cubic unit
    A unit cube with side lengths that are standard measurement units that is used to measure volume.
  • rectangular prism
    A solid figure which has six faces that are rectangles.
  • unit cube
    A cube whose sides are 1 unit long, used to measure volume.
  • volume
    The number of unit cubes that fill a solid figure without gaps or overlap.