standard_description: Interpret and compute quotients of fractions, and solve word problems involving division of fractions by fractions, e.g., by using visual fraction models and equations to represent the problem. For example, create a story context for (2/3) ÷ (3/4) and use a visual fraction model to show the quotient; use the relationship between multiplication and division to explain that (2/3) ÷ (3/4) = 8/9 because 3/4 of 8/9 is 2/3. (In general, (a/b) ÷ (c/d) = ad/bc.) How much chocolate will each person get if 3 people share 1/2 lb of chocolate equally? How many 3/4-cup servings are in 2/3 of a cup of yogurt? How wide is a rectangular strip of land with length 3/4 mi and area 1/2 square mi?
problem_activity: Problem 1
The same image of a cat is shown at three different zoom levels on a computer.
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What do you notice about what happens to the scale as you zoom in and out on the image?
Problem 2
Your computer shows you a map of Washington Park in Eugene, Oregon. The scale in the bottom right corner of the map tells us that the length of the bar represents 200 feet on the map.
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Clicking a resizing button on the computer screen will result in an image of Washington Park, where the exact same-sized bar now represents 150 feet.
a.   Do you think the size of Washington Park under the 150 ft. scale will appear smaller or larger than it was under the 200 ft. scale?
b.   Draw an accurate picture/map of Washington Park under this new 150 ft. scale. Use the handout.
c.   Was your guess in part (a) correct? Can you explain why the size of the map changed as it did?


aligns: no