Unit 5 Making Sense of Multiplication of Fractions

In Unit 5 students will:

  • Interpret a fraction as division of the numerator by the denominator (a/b= a ÷b). Solve word problems involving division of whole numbers leading to answers in the form of fractions or mixed numbers, e.g., by using visual fraction models or equations to represent the problem.
  • Apply and extend previous understandings of multiplication to multiply a fraction or whole number by a fraction.
    • a. Interpret the product (a/b) x q s a parts of a partition of q into b equal parts; equivalently, as the result of a sequence of operations a x q ÷ b
  •  Solve real world problems involving multiplication of fractions and mixed numbers, e.g., by using visual fractions models or equations to represent the problem
  • Interpret multiplication as scaling (resizing) by:
    • a. Comparing the size of a product to the size of one factor on the basis of the size of the other factor, without performing the indicated multiplication.
    • b. Explaining why multiplying a given number by a fraction greater than 1 results in a product greater than the given number (recognizing multiplication by whole numbers greater than 1 as a familiar case); explaining why multiplying a given number by a fraction less than 1 results in a product smaller than the given number; and relating the principle of a fraction equivalence a/b = (nxa)/(nxb) to the effect of multiplying a/b by 1.

By the end of Unit 5 your child should be able to answer the following question.

  •  How can I use repeated addition to help me understand multiplication of fractions?
  •  In what real world context would a fraction be multiplied by a whole number?
  •  In what real world context would a fractional part of a fraction exist?

The following videos support some of the topics covered in Unit 5.

 

  •  Multiplying  Fractions  By a Whole Number With Models

  • Multiplying Fractions By a Whole Number Using repeated addition.

  • Multiplying a Fraction by Fraction Using the Area Model

  • Multiplying a Fraction by a Whole Number Using the Area Model