Key Points: Overall Conclusion If the scale factor is represented by k, then the area of the scale drawing is k times the corresponding area of the original drawing.
Example 1 What percent of the area of the large square is the area of the small square?
Determine the area of the shaded region in the smaller scale drawing.
Example 4 Use Figure 1 below and the enlarged scale drawing to justify why the area of the scale drawing is k Exercise 1 1.
For Dwight and Dierdre it could look like the following: We organized the information the same way for both runners, but can see that for Dwight we made our ratios “horizontally” but for Dierdre we made them “vertically.” Of course we could do either problem both ways—and get the same result.
Having said that, one approach is usually better, and depends on what else you want to know.The key is whether students understand what they are doing—that they’re reasoning about the situation and not simply following a recipe.One way to help this happen is to take the time to compare the two approaches to some problem the class has done.Opener: As students enter the room, they will immediately pick up and begin working on the opener – Instructional Strategy - Process for openers This method of working and going over the opener lends itself to allow students to construct viable arguments and critique the reasoning of others, which is mathematical practice 3. I let tables discuss this problem for a few moments and take volunteers to share out their answers to the group.Learning Target: After completion of the opener, I will address the day’s learning targets to the students. There are many situations where problems can be solved with a firm understanding of ratio and scale value.This resource package contains a variety of activities designed to introduce, explore and consolidate learning in the use of ratio and scale factor notation and use methods involving conversion, mixing, measuring, scaling and comparing quantities and concentrations.Help students decide for themselves what works best, what makes things easier or more understandable.For example, if you want to estimate distances for times other than an hour, or times for distances other than 3 miles, the “unit rate” scheme—Dwight—will let you write () and solve lots of problems easily.For today’s lesson, the intended target is “I can determine scale factor.” Students will jot the learning target down in their agendas (our version of a student planner, there is a place to write the learning target for every day). Activating Prior Knowledge: To get this lesson started, I like to pose the following problem: The scale of a blueprint is 1 inch = 10 feet.