1. LEARNING GOALS – LESSON 7:5
Warm Up
Convert each measurement
a. 6 ft 3 in. to inches b. 5m 38 cm to centimeters
Find the area and perimeter of a square with sides of length 13 cm.
Find the area and perimeter of a rectangle with sides of 5.8m & 2.5m.
LEARNING GOALS – LESSON 7:5
7.5.1: Use ratios to make indirect measurements.
7.5.2: Use scale drawings to solve problems.
7.5.3: Use rations to find perimeter and area
______________ measurement is any method that uses:
Example 1: Measurement Application
This here is a picture of Larry. Larry claims
that the fish he caught were a total of 6.5 ft
in length! If Larry is actually 5’ 11”, use
indirect measurement to determine if he
is fibbing.

2. Example 2A: Solving for a Dimension
A ___________ drawing represents an object as smaller than or larger than its actual size. The drawing’s scale is the ___________ of any length in the drawing to the corresponding actual length.
Example 2A: Solving for a Dimension
On a Wisconsin road map, Kristin measured a distance of 11⅛ in. from Madison to Wausau. The scale of this map is 1inch:13 miles. What is the actual distance between Madison and Wausau to the nearest mile?
Find the actual distance
between City Hall and El Centro College.
Example 2B: Making a Scale Drawing
The rectangular central chamber of the Lincoln Memorial is 70 ft long and 60 ft wide. Make a scale drawing of the floor of the chamber using a scale of 1 in.:20 ft.

3. Example 3: Using Ratios to Find Perimeters and Areas
A. Given that ∆LMN ~ ∆QRT, find the perimeter P and area A of ∆QRS.
∆ABC ~ ∆DEF, BC = 4 mm, and EF = 12 mm. If P = 42 mm and
A = 96 mm2 for ∆DEF, find the perimeter and area of ∆ABC.