Lesson 1 Problem 1 An elevator travels 310 feet in 10 seconds. At that speed, how far can this elevator travel in 12 seconds? Explain your reasoning. Solution 310÷10=31, 31⋅12=327. 327 feet. so the elevator travels 31 feet per second. and Problem 2 Han earns $33.00 for babysitting 4 hours. At this rate, how much will he earn if he babysits for 7 hours? Explain your reasoning. Solution 33÷4=8.25, He will earn $57.75 in 7 hours. so the hourly rate is $8.25. If he earns $8.25 8.25⋅7 every hour, he will earn or $57.75. Problem 3 The cost of 5 cans of dog food is $4.35. At this price, how much do 11 cans of dog food cost? Explain your reasoning. Solution 4.35÷5=0.87, 0.87⋅11=9.57. 11 cans cost $9.57. so each can costs 87 cents, and Problem 4 A restaurant has 26 tables in its dining room. It takes the waitstaff 10 minutes to clear and set 4 tables. At this rate, how long will it take the waitstaff to clear and set all the tables in the dining room? Explain or show your reasoning. Solution It will take 65 minutes, or 1 hour and 5 minutes. Sample strategy: number of tables time in minutes
Lesson 1 Problem 1 An elevator travels 310 feet in 10 seconds. At that speed, how far can this elevator travel in 12 seconds? Explain your reasoning. Solution 327 feet. 310÷10=31, so the elevator travels 31 feet per second. and 31⋅12=327. Problem 2 Han earns $33.00 for babysitting 4 hours. At this rate, how much will he earn if he babysits for 7 hours? Explain your reasoning. Solution He will earn $57.75 in 7 hours. 33÷4=8.25, so the hourly rate is $8.25. If he earns $8.25 every hour, he will earn 8.25⋅7 or $57.75. Problem 3 The cost of 5 cans of dog food is $4.35. At this price, how much do 11 cans of dog food cost? Explain your reasoning. Solution 11 cans cost $9.57. 4.35÷5=0.87, so each can costs 87 cents, and 0.87⋅11=9.57. Problem 4 A restaurant has 26 tables in its dining room. It takes the waitstaff 10 minutes to clear and set 4 tables. At this rate, how long will it take the waitstaff to clear and set all the tables in the dining room? Explain or show your reasoning. Solution It will take 65 minutes, or 1 hour and 5 minutes. Sample strategy: number of tables time in minutes
practice_problems_unit_3.docx