Name. # s. Sim made 78 scarves. He sold t scarves on Saturday and 30 scarves on Sunday. Write an expression to describe how many scarves Sim has left.

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1 Homework Problems Name Team Name Team Complete? Team Did Not Agree On Questions # s Quick Look Today we wrote an algebraic expression to describe a real-world situation. Then, we evaluated the expression at a specific value. Here s an example! Sim made 78 scarves. He sold t scarves on Saturday and 30 scarves on Sunday. Write an expression to describe how many scarves Sim has left. 78 t 30 or 78 (t + 30) Sim had 78 scarves. If he sold 20 on Saturday and t on Sunday, he sold 20 + t scarves in all. So to find how many he had left, subtract the scarves he sold in all from the total amount of scarves he made. Evaluate the expression when t = 45 If t = 45, that means he sold 45 scarves on Saturday. Replace t with 45 and evaluate using the Order of Operations. 78 (t + 30) 78 ( ) = 3; Sim has 3 scarves left. 1) At an amusement park, x people are on a roller coaster. 40% of the people are kids under the age of 13. a. Write an algebraic expression to describe how many people on the roller coaster are 13 and younger. b. Evaluate the expression for x = Success for All Foundation Homework Problems 1

2 2) The local car wash charges $8.00 to wash the outside of the car, and an additional $0.50 per minute to clean the inside. a. Write an algebraic expression to describe how much the car wash makes if a person gets both the inside and outside of their car cleaned. b. How much does it cost a customer that has the outside of his car washed and it takes 20 minutes to clean the inside? 3) At a town hall meeting, w people came to vote on a new town ordinance. 3 2 of the people voted yes. 5 voters abstained from the vote. a. Write an algebraic expression to describe the number of people who voted no. Explain your thinking. b. Evaluate the expression if w = 45. 4) Janet donated pencils to four different disadvantaged schools and distributed them evenly. a. Write an algebraic expression to describe how many pencils each school received. Explain your thinking. b. How many pencils did each school get if Janet donated 8,000 pencils? 5) At the golf tournament, g golfers scored well enough to advance to the next round. 66 players did not advance. a. Write an algebraic expression to describe how many golfers there were in total Success for All Foundation Homework Problems

3 b. Evaluate the expression for g = 34. Explain your thinking. 6) Ms. Sager donated 128 ounces of glue to the 6th grade art class. Mr. McEvoy donated 256 ounces of glue. The 6th grade art class has z students. a. Write an algebraic expression that describes the amount of glue each student could have if the glue is divided equally. b. Evaluate the expression for z = 15. 7) A restaurant paid their employees $150,000 from their total revenue. a. Write an algebraic expression that describes how much money the restaurant has left after they pay their employees. b. How much money do they have left if their total revenue income was $400,000? 8) To dock a boat at Jerry s Waterside Dock, it costs $ in advance, and a $150 each month the boat is docked in the spot. a. Write an algebraic expression that describes how much it will cost to dock a boat. b. How much will it cost if you want to dock a boat for 12 months? Explain your thinking Success for All Foundation Homework Problems 3

4 Mixed Practice 9) Write an algebraic expression for the math phrase. 10) Write an expression to complete the pattern for the table. 2 less than the product of 4 and g 11) Add = 7 12) Write one unit rate to describe the conversion between Teaspoons and Tablespoons. Word Problem 13) Each class has g reading groups. Each reading group has 5 students. Each student needs 5 binders. Each binder has 5 tabs. Write an expression to describe the amount of tabs each class needs. How many tabs does a class with 4 reading groups in it need? Explain your thinking Success for All Foundation Homework Problems

5 For the Guide on the Side Today your student wrote algebraic expressions to represent real-life situations. He or she built on writing algebraic expressions from mathematical statements to apply expressions to real-life problems. Your student defined an unknown quantity with a variable and then wrote an expression paying close attention to Order of Operations. Your student then evaluated the expression at a specific value. Your student should be able to answer the following questions about writing and evaluating expressions: 1) What s going on in the problem? 2) Explain why you wrote the expression this way. Why are the numbers, variables, and operations in this particular order? 3) Explain how the value of the expression will change when the value of the variable changes. Here are some ideas to work with writing and evaluating expressions: 1) Write an algebraic expression to describe a real-life situation. It could be about your life, school community, or world! Then, evaluate your expression at different values. What happens to the value of the expression as you change the value of the variable? 2) Watch a video from Khan Academy to review evaluating expressions: Success for All Foundation Homework Problems 5

6 Homework Answers 1) a. Possible answer: The number of kids under the age of 13 is 0.4x, where x represents the total number of people on the roller coaster. b. If there are 30 people on the roller coaster, then there are 12 children under the age of 13. 2) a. Possible answer: The cost to get the inside and outside of your car cleaned is k, where k is equal to the number of minutes it takes to clean the inside. b. It will cost $18.00 if the car takes 20 minutes to clean inside. 3) a. Possible answer: The number of people who vote no is 3 1 w 5, where w represents the total number of people at the meeting. Possible explanation: I saw that 3 2 of the people said yes, meaning 3 1 did not vote yes. However, 5 people abstained, so that means 5 less than 3 1 of the people voted no. b. If there are 45 people at the meeting in total, there are 10 people that voted no. 4) a. Possible answer: The number of pencils each schools receives is s 4 or 4 s where s is equal to the total number of pencils Janet donated. Possible explanation: The value that is missing is how many pencils Janet donated in total, so I represented that with the variable s. Then I divided s by 4 (because there are four schools splitting the donation) to find out how many pencils each school received. b. If Janet donated 8,000 pencils, each of the four schools received 2,000. 5) a. Possible answer: The total number of golfers in the tournament is g + 66, where g represents the number of golfers who advanced to the next round. b. If 34 golfers advanced to the next round, there were 100 golfers in all to start the tournament. Possible explanation: To find how many golfers there were in the tournament in total, I substituted 34 for g and added 66 to get ) a. Possible answer: The amount of glue each student receives is ( ) z, where z represents the total number of students. b. There would be 25.6 ounces of glue for each student if there are 15 students in the class. 7) a. Possible answer: The restaurant has p $150,000 after they pay their employees, where p is equal to the total revenue. b. If their total revenue was $400,000, the restaurant would have $250,000 remaining after paying their employees. 8) a. Possible answer: The total cost to dock the boat is y, where y is equal to the number of months the boat is docked. b. It will cost $2,050 to dock the boat for 12 months. Possible explanation: To find the total cost of docking the boat for 12 months, I substituted 12 for y and followed the Order of Operations by first multiplying = 1,800, then adding 250 to get $2,050. Mixed Practice 9) 4x 2 10) y 2 or 2 y Word Problem 11) ) 3 teaspoons per 1 tablespoon. 13) 5 3 g or 125 g. If the class has 4 reading groups, they need 500 tabs. Possible explanation: 5 students who need 5 binders each with 5 tabs each means multiplication, that s or 5 3. Then I multiplied that by the number of reading groups in each class, g. If g = 4 that means that each class has 4 reading groups. I substituted 4 for g and used the Order of Operations to evaluate. I got 500 which means that each class needs 500 tabs Success for All Foundation Homework Problems