4-2 Unit Rates and Proportional Reasoning

Video Tutor Help Finding a unit rateFinding a unit rate (4-2) Comparing unit ratesComparing unit rates (4-2) Finding Unit Rates Khan Academy Find a unit rate

Video Tutor Help Writing ratios in three ways Writing equivalent ratios Finding a unit rate Comparing unit rates Identifying whether two ratios are proportional Solving proportions using cross products Solving proportions using number sense or mental math Using similar figures to find indirect measurement Using proportion to find unknown length in similar figures Finding distances on maps using scale

Worksheets Daily Notetaking Guide Worksheets Version A Practice, Guided Problem Solving Lesson 4-2 Practice 4-2 Guided Problem Solving 4-2

Vocabulary Practice Vocabulary (Electronic) Flash Cards Equations and Inequalities Vocabulary 4A: Graphic Organizer Vocabulary 4B: Reading Comprehension Vocabulary 4C: Reading/Writing Math Symbols Vocabulary 4D: Visual Vocabulary Practice Vocabulary 4E: Vocabulary C Vocabulary 4F: Vocabulary Review Puzzle

Additional Lesson Examples Step-by-Step Examples Lesson 4-2

Lesson Readiness Lesson Quiz Problem of the Day Lesson 4-2

Rate A rate is a special kind of ratio. It is a comparison of two quantities with types of units. $5 for 2 pounds Dollars and pounds are different types of units. 130 miles in 2 hours Miles and hours are different types of units.

Unit Rate When a rate is simplified so it has a denominator of 1, it is called a unit rate. An example of a unit rate is $6.50 per hour, which means $6.50 per 1 hour.

Example 1-3a Shopping A 12-oz bottle of cleaner costs $4.50. A 16-oz bottle of cleaner costs $6.56. Which costs less per ounce? Find and compare the unit rates of the bottles. Divide the numerator and denominator by 12 to get a denominator of 1. For the 12-oz bottle, the unit rate is $0.38 per ounce. Find Unit Rate

Example 1-3b Divide the numerator and denominator by 16 to get a denominator of 1. For the 16-oz bottle, the unit rate is $0.41 per ounce. Answer: The 12-oz bottle has the lower cost per ounce.

Find the unit rate: earn $33 for 4 hours of work. = 8.25 Divide the first quantity by the second quantity. dollars33 hours4 The unit rate is, or $8.25 per hour. $ hour LESSON 4-2 Unit Rates and Proportional Reasoning Additional Examples

Example 1-3a READING Yi-Mei reads 141 pages in 3 hours. How many pages does she read per hour? Write the rate that expresses the comparison of pages to hours. Then find the unit rate. Answer: Yi-Mei reads an average of 47 pages per hour. Divide the numerator and denominator by 3 to get a denominator of 1. Find a Unit Rate

Use the unit price to find the total price: 7 yd of ribbon at $.39 per yard. The total price of 7 yd of ribbon is $2.73. = $2.73 unit price number of units = total price LESSON 4-2 $.39 7 Unit Rates and Proportional Reasoning Additional Examples

Find each unit price. Then determine the better buy. 3 lb of potatoes for $.89 5 lb of potatoes for $1.59 Divide to find the unit price of each size. Since $.30 < $.32, 3 lb of potatoes for $.89 is the better buy. price number of lb $.30/lb $.89 3 price number of lb $.32/lb $ LESSON 4-2 Unit Rates and Proportional Reasoning Additional Examples