4.1.2 Scale Drawings, How can I use a scale drawing? p192 Reason abstractly and quantitatively to evaluate ratios in order to determine similarity.  Attend to precision you draw representations of problems and compare ratios. LO: I will use lengths and areas to solve problems involving scale drawings of geometric figures. Introduction In a scale drawing, it is important to decide on the unit of measure.  Maps made in the United States usually represent distances in miles, but they certainly cannot use actual miles as the unit of measure.  Otherwise, a map of Pennsylvania would be over 250 miles long and 450 miles wide!  A map includes a scale, which shows the units in which the map is drawn.  An example is shown at right. Maps are examples of scale drawings.  They are reduced versions of the original regions.  A map is similar to the original region, because it has the same shape.  Because of this, maps conveniently allow users to determine distances between two points. 

Did she really measure 14 miles? 4-11 Suppose Eulalia uses a map of Pennsylvania to determine that Valley Forge is 14 miles from downtown Philadelphia. Did she really measure 14 miles? Explain how she probably determined the distance.

Take what you know, and solve for what you don’t know yet. 4-12 Scale Factor 𝒄𝒐𝒑𝒚 𝒐𝒓𝒊𝒈𝒊𝒏𝒂𝒍 Multiplier

Take what you know, and solve for what you don’t know yet. 4-13 Read. Scale Factor 𝒄𝒐𝒑𝒚 𝒐𝒓𝒊𝒈𝒊𝒏𝒂𝒍 Multiplier Scale _____ ft. = _____ in. Living room scale drawing (in.) Living room actual (ft.) Living room carpet costs ______

Take what you know, and solve for what you don’t know yet. 4-14 Scale Factor 𝒄𝒐𝒑𝒚 𝒐𝒓𝒊𝒈𝒊𝒏𝒂𝒍 Multiplier

Take what you know, and solve for what you don’t know yet. 4-15 Scale Factor 𝒄𝒐𝒑𝒚 𝒐𝒓𝒊𝒈𝒊𝒏𝒂𝒍 Multiplier Closure Reference 4-14 What is the area of the rectangle in square miles? scale of 1foot = 5 miles

 4.1.2 1 2 3 4 5 6 7 8 9 11 12.a. 12.b. 13.a. 13.b. 13.c. 13.d. 14. HW 4.1.2 #12 HW 4.1.2 #16-20

original : copy ~ original : copy 4.1.2 Scale Drawings, How can I use a scale drawing? p192 7.G.1 Reason abstractly and quantitatively to evaluate ratios in order to determine similarity.  Attend to precision you draw representations of problems and compare ratios. 4.1.2 will investigate how to enlarge and reduce figures so that they maintain their same shape.  Your work with similar figures and scale drawings, such as maps and blueprints, will lay the foundation for much of the rest of the chapter. original : copy ~ original : copy Find the scale factor from the larger rectangle to the smaller rectangle, if the two rectangles are similar. a. 5:1 b. 5:6 c. 6:5 d. 6:7

1mi : 5280 ft. 20 in. : 80 ft. 1 in. : 18 in. 100 in. : 10 ft. Reasoning Analyze whether each scale factor reduces, enlarges, or preserves the size of the actual object. Scale Factor Simplified Analysis of Dimension Change 1mi : 5280 ft. 20 in. : 80 ft. 1 in. : 18 in. 100 in. : 10 ft. 4 ft : 15 in. 100 cm : 1 m 1 cm : 10 mm 10 ft : 24 in.

I know that it takes a fourteen quarters stacked on top of each other to make an inch. What is your value in quarters? Would you be worth more if they were stacked or laid end to end?