Rearrange the shaded parts
into a unit square.Since ^24 or ^12 of the unit square is shaded, 2 ×^14 =^12.
Find 1^23 × ^12 using a model.
Draw two squares side by side. (^123)
1
2
Shade a rectangle that is 1 ^23 units
long and ^12 unit wide.
Rearrange the shaded parts into
a unit square.
Since ^56 of the unit square is shaded, 1 32 ×^12 =^56.
and Apply
Write a multiplication sentence for the product shown in each model.
Find each product using a geoboard or an area model.- 41 × 31 4. 21 × ^12 5. ^34 × ^12 6. 32 × ^14
- 3 × 32 8. 2 × ^25 9. 1 ^14 × ^15 10. 2 ^12 × ^34
the Results
- MAKE A CONJECTURE Refer to Activities 1–3. How are the numerators and
denominators of the factors related to each product? - E WRITE MATH Write a rule you can use to multiply two fractions.
Lesson 3A Multiply and Divide Fractions 159158_165_C3L3_895130.indd 159 12/31/09 12:40 PM