Ratios, Rates and Percents Lesson 5 Ratios, Rates and Percents Perimeter and Area

Warm-Up Determine whether or not each sequence is a geometric sequence. Explain your choice. 2, 6, 18, 54, … 2, 4, 6, 8, … Complete each conversion. 4 yards = _____ feet 20 millimeters = _____ centimeters

Target: Convert measurements to find perimeter and area.

Vocabulary Perimeter: The distance around a figure. Area: The number of square units needed to cover a surface.

Example 1 Find the perimeter of the rectangle in: a. meters b. centimeters a. Add lengths of the four sides: b. Convert using 1 meter = 100 centimeters Add lengths of sides:

Example 2 Find the area of the triangle in: a. feet b. inches a. Triangle Area Formula: b = 4, h = 3 ; Calculate the area The area is 6 square feet. b. Convert using 1 foot = 12 inches Calculate the area: The area is 864 square inches.

Example 3a One rectangle has sides twice as long as another rectangle. Find the smaller perimeter to the larger perimeter. Perimeter of small rectangle: 1 + 3 + 1 + 3 = 8 cm Perimeter of large rectangle: 2 + 6 + 2 + 6 =16 cm Ratio of the smaller perimeter to the larger perimeter:

Example 3b One rectangle has sides twice as long as another rectangle. Find the ratio of the smaller area to the larger area. Area of small rectangle: 3 × 1 = 3 square centimeters Area of large rectangle : 6 × 2 = 12 square centimeters Ratio of smaller area to the larger area:

Exit Problems Find the perimeter of the rectangle in yards. 2 yd 4 yd Find the perimeter of the rectangle in yards. Find the perimeter of the rectangle in feet. Find the area of the rectangle in square yards. Find the area of the rectangle in square feet.

Communication Prompt For a square that is 1 centimeter by 1 centimeter, how do you find its perimeter in terms of millimeters? its area in terms of square millimeters?