Copy planner 7-1 Ratios and Proportions Warm Up Pre-Algebra 7-1 Ratios and Proportions Copy planner Warm Up Write each fraction in lowest terms. 14 16 1. 7 8 24 64 2. 3 8 9 72 3. 1 8 45 120 4. 3 8

Learn to find equivalent ratios to create proportions.

Vocabulary ratio equivalent ratio proportion

Ratios can be written in several ways. A colon is often used Ratios can be written in several ways. A colon is often used. 90:3 and name the same ratio. Reading Math 90 3

Find two ratios that are equivalent to each given ratio. = 9 27 = 9 • 2 27 • 2 18 54 A. 9 27 = = 9 ÷ 9 27 ÷ 9 1 3 Two ratios equivalent to are and . 9 27 18 54 1 3 = 64 • 2 24 • 2 64 24 = 128 48 Two ratios equivalent to are and . 64 24 128 48 8 3 B. 64 24 = = 64 ÷ 8 24 ÷ 8 8 3

Ratios that are equivalent are said to be proportional, or in proportion. Equivalent ratios are identical when they are written in simplest form.

Simplify to tell whether the ratios form a proportion. Since , the ratios are in proportion. 1 9 = 3 27 A. and 2 18 3 27 = = 3 ÷ 3 27 ÷ 3 1 9 2 18 = = 2 ÷ 2 18 ÷ 2 1 9 12 15 B. and 27 36 12 15 = = 12 ÷ 3 15 ÷ 3 4 5 Since , the ratios are not in proportion. 4 5  3 27 36 = = 27 ÷ 9 36 ÷ 9 3 4

Lesson Quiz: Part 1 Find two ratios that are equivalent to each given ratio. 4 15 1. 8 30 12 45 Possible answer: , 16 42 24 63 Possible answer: , 8 21 2. Simplify to tell whether the ratios form a proportion. 16 10 3. 32 20 8 5 = ; yes and 36 24 4. 28 18 3 2 14 9  ; no and

Lesson Quiz: Part 2 5. Kate poured 8 oz of juice from a 64 oz bottle. Brian poured 16 oz of juice from a 128 oz bottle. What ratio of juice is missing from each bottle? Are the ratios proportional? 8 64 16 128 and ; yes, both equal 1 8