standard_description: Interpret multiplication as scaling (resizing), by:
- 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 fraction equivalence a/b = (n×a)/(n×b) to the effect of multiplying a/b by 1.
- 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.
problem_activity: Problem 1
Solve each problem in two different ways.
a.
$${3{1\over3} \times 1{1\over4}}$$
b.
$${5{2\over5} \times 3{4\over9}}$$
Problem 2
Which strategy was more efficient for each problem above? Explain.


aligns: yes