Modeling Multiplication of a Fraction by a Fraction Measurement Modeling Multiplication of a Fraction by a Fraction

Multiplying Fractions & Whole Numbers The operation of multiplying two fractions requires us to multiply numerators and denominators. Example: 1/3 x 3/4 = 3/12 = 1/4

Multiplying Fractions & Whole Numbers When we multiply whole numbers we can model the multiplication to arrive at the answer. 3 Example: 4 x 3 4

Multiplying Fractions & Whole Numbers We can also model the multiplication of fractions in the same way.. Example: 2/3 of a class are boys. Of these, 3/4 are wearing running shoes. What fraction of the class is boys wearing running shoes?

Multiplying Fractions & Whole Numbers Example: 2/3 of a class are boys. Of these, 3/4 are wearing running shoes. What fraction of the class is boys wearing running shoes? 3/4 of 2/3 are boys wearing running shoes. 3/4 x 2/3

Multiplying Fractions & Whole Numbers We start with the group, in this case the second fraction, 2/3. 3/4 x 2/3 2/3

Multiplying Fractions & Whole Numbers Then we divide the square in the other direction to model multiplication by 3/4. 2/3 3/4

Multiplying Fractions & Whole Numbers How many small units are shaded under both fractions out of the total square? 2/3 1 2 3 4 3/4 5 6

Multiplying Fractions & Whole Numbers 6 small units are shaded by both fractions out of 12 total in the whole square. 2/3 3/4

Multiplying Fractions & Whole Numbers 3/4 x 2/3 3/4 x 2/3 = 6/12 2/3 3/4

Multiplying Fractions & Whole Numbers Try this: 1/3 of 1/4 =

Multiplying Fractions & Whole Numbers How about this: 2/3 of 3/5 =