1. Modeling Multiplication of a Fraction by a Fraction
Measurement
Modeling Multiplication of
a Fraction by a Fraction

2. 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

3. 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

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?

5. 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

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

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

8. 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

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

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

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

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