Unit Rates and Proportional Reasoning LESSON 5 2

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Unit Rates and Proportional Reasoning LESSON 5 -2 Course 2 Problem of the Day

Unit Rates and Proportional Reasoning LESSON 5 -2 Course 2 Problem of the Day Solve using distributive property 1) 8 y -(2 y -3) = 9 2) 6(x + 4) -2 x = -8 1) y = 1 2) X = -8 Lesson Main Lesson 5 -2 Feature

Unit Rates and Proportional Reasoning LESSON 5 -2 Course 2 Recall (For help, go

Unit Rates and Proportional Reasoning LESSON 5 -2 Course 2 Recall (For help, go to Lesson 5 -1. ) What is a ratio? - Compares two quantities measured in the same unit - It can be written as a fraction - It has no units Lesson Main Lesson 5 -2 Feature

Unit Rates and Proportional Reasoning LESSON 5 -2 Course 2 What are you going

Unit Rates and Proportional Reasoning LESSON 5 -2 Course 2 What are you going to learn? (For help, go to Lesson 5 -1. ) 3 main concepts – 1) Finding unit rate 2) Finding total cost using unit cost 3) Using unit cost to compare and find out better buy Lesson Main Lesson 5 -2 Feature

Unit Rates and Proportional Reasoning LESSON 5 -2 Course 2 RATE? Rate compares two

Unit Rates and Proportional Reasoning LESSON 5 -2 Course 2 RATE? Rate compares two quantities measured in different units It is a form of ratio in which the two terms are in different units Unit Rate – Rate for one unit of a given quantity. Simply put, rate which has denominator of 1. Examples? mi/hr, $/kg, m/s To find the unit rate, simply divide the first quantity by the second. Unit Cost – A unit rate that gives cost per unit. Lesson Main Lesson 5 -2 Feature

Unit Rates and Proportional Reasoning LESSON 5 -2 Course 2 Additional Examples Find the

Unit Rates and Proportional Reasoning LESSON 5 -2 Course 2 Additional Examples Find the unit rate: earn $33 for 4 hours of work. dollars 33 hours 4 = 8. 25 Divide the first quantity by the second quantity. $8. 25 The unit rate is 1 hour , or $8. 25 per hour. Quick Check Lesson Main Lesson 5 -2 Feature

Unit Rates and Proportional Reasoning LESSON 5 -2 Course 2 Additional Examples Use the

Unit Rates and Proportional Reasoning LESSON 5 -2 Course 2 Additional Examples Use the unit price to find the total price: 7 yd of ribbon at $. 39 per yard. $. 39 • 7 = $2. 73 unit price • number of units = total price The total price of 7 yd of ribbon is $2. 73. Quick Check Lesson Main Lesson 5 -2 Feature

Unit Rates and Proportional Reasoning LESSON 5 -2 Course 2 Additional Examples Find each

Unit Rates and Proportional Reasoning LESSON 5 -2 Course 2 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. price number of lb $. 89 3 $. 30/lb price number of lb $1. 59 5 $. 32/lb Remember: Better buy has the smallest price / unit Since $. 30 < $. 32, 3 lb of potatoes for $. 89 is the better buy. Lesson Main Lesson 5 -2 Quick Check Feature

Unit Rates and Proportional Reasoning LESSON 5 -2 Course 2 Using conversion factors We

Unit Rates and Proportional Reasoning LESSON 5 -2 Course 2 Using conversion factors We are going to use ratios to convert a measurement from one system to another. Conversion factor is a rate that equals 1. Note: This method of canceling units is quite useful especially in Science. This technique is called ‘unit analysis’ or ‘dimensional analysis’ – I’ve introduced this to you as “multiplying by a fraction equal to 1” Main principle – multiplying / dividing something by 1 doesn’t change the value. Lesson Main Lesson 5 -2 Feature

Unit Rates and Proportional Reasoning LESSON 5 -2 Course 2 Lesson Quiz 1. It

Unit Rates and Proportional Reasoning LESSON 5 -2 Course 2 Lesson Quiz 1. It took Anthony 5 h 45 min to complete a 25 -mi walkathon. What was his average speed in miles per hour? Round your answer to the nearest hundredth. 4. 35 mi/h 2. A 20 -lb bag of dog food costs $21. 50. A 30 -lb bag of the same dog food costs $32. 90. Find each unit price. Then determine the better buy. $1. 08/lb; Lesson Main $1. 10/lb; 20 lb for $21. 50. Lesson 5 -2 Feature

Unit Rates and Proportional Reasoning LESSON 5 -2 Course 2 Lesson Quiz 1. If

Unit Rates and Proportional Reasoning LESSON 5 -2 Course 2 Lesson Quiz 1. If a car travels 45 miles in 30 min, what is the rate at which the car is travelling? 90 mi/hr or 1. 5 mi/min 2. If John bought 2. 5 kg of rice for $7. 5, what is the unit price of rice? $3/kg 3. It takes 30 min for a tap to fill one bucket, how much time (in hrs) would it take to fill 6 buckets? Total 3 hrs 4. You can buy 28 fl oz of fruit juice for $1. 69 or 64 fl oz for $3. 19. Which size is a better buy? 64 fl oz for $3. 19 Lesson Main Lesson 5 -2 Feature

HOMEWORK Course 2 Homework: Lesson 5 -2: p. 234 -236: 1, 6 – 28

HOMEWORK Course 2 Homework: Lesson 5 -2: p. 234 -236: 1, 6 – 28 e, 29 p. 236: # 1 -9 all – This should be review. Show all work. Lesson Main Lesson Feature