Answer each of the following. 1) What is the difference between a ratio and a rate? 2) What is a unit rate? 3) What is a proportion?

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1 ARE YOU READY? 7 th Grade Accelerated Chapter 7 Vocabulary Name: Date: Block: Answer each of the following. 1) What is the difference between a ratio and a rate? 2) What is a unit rate? 3) What is a proportion? 4) What is the cross products property? What is it used for? 5) What is the difference between a scale model and a scale drawing? 6) What is scale? How is it written? 7) Define percent: 8) Describe how you turn a percent into a decimal: 9) Describe how you turn a percent into a fraction: 10) What is a discount? 11) What is markup? How does it relate to the wholesale price and the retail price? 12) What is the simple interest formula? 1

2 Skills Use the following table to answer the questions. Write all ratios in simplest form. Number of Students Earning an A on the Last Test Math 1 Math 2 Math 3 Math 4 Mr. Doyle Mrs. Eschman Mrs. Plump ) Write a ratio of the students who earned A s in Mr. Doyle s first period class to Mrs. Eschman s first period class. 14) Write a ratio of the students who earned A s in Mrs. Eschman s second period class to Mrs. Plump s second period class. 15) Write a ratio of the students who earned A s in Mr. Doyle s first period class to all of Mr. Doyle s students who earned A s. 16) Write a ratio of the students who earned A s in all of Mrs. Plump s classes to the students who earned A s in all of the classes. Write the rate as a unit rate/find the average speed. Round to the nearest tenth. 17) 68dinners 4hours 18) 300 miles in 6 hours 19) 640 feet in 5 minutes 20 seconds 20) Find the unit rate to determine which is a better buy: 36 oz. for $ oz. for $ oz. for $3.90 2

3 Solve for x: 21) 2 9 = x ) 3x 7 = x Write and solve a proportion for each of the following problems. Round to the nearest tenth if necessary. 23) What number is 38% of 125? 24) Four is 30% of what number? 25) What percent of 80 is 15? Write and solve a proportion for each of the following problems. Round to the nearest tenth if necessary. Find the percent of increase or decrease: 26) Original amount: 50; New amount: 85 27) Original amount: 15; New amount: 8 Find the new amount: 28) A 19% decrease of 78 29) A 150% increase of 90 Find the new price: 30) Original price: $56; Discount: 20% 3

4 31) Wholesale price: $135; Mark-up: 230% 32) Food bill before tax: $79.33; Tax: 7.5%; Tip: 15% 33) ABCD and EFGH are Similar. Find the length of side AB. Applications Write and solve a proportion for each of the following problems. Show all work and be sure to label your answers! 34) The average 7 th grader uses his/her phone for 52.5 hours in 7 days. How many hours would they use their phone for in 15 days? 35) If an airplane in a 1 in.:4 ft scale drawing is 7.5 inches long, how long is the actual airplane? 36) On a map, the distance between two cities is 7.3 cm. What is the actual distance between these two cities if the map scale is 1 cm:50 km? 37) A landscaper's scale model drawing of a garden has a length of 12 inches and a width of 10 inches. If the width of the garden is 50 feet, what is the scale of the drawing to the garden? Express your answer as a scale with the same units. 4

5 38) If the price of gold went from $460 an ounce to $483 an ounce in one week, what was the percent change in the price of gold? 39) Olivia wants to buy a necklace. The necklace has a list price of $41, is on sale for 15% off, and the sales tax is 6%. How much will Olivia pay for the necklace? 40) A retailer buys a coat in bulk at a unit price of $45 (each). The coat is marked up 128% to sell in the store. If the sales tax is 7.5%, how much will you pay for the coat? 41) Carson has $1,032 in his savings account. If the bank pays 3.5% simple interest on savings, how much does he have at the end of 18 months? 42) A balloon holds 4.2 cubic feet of air. The balloon is blown up larger to hold 5.6 cubic feet of air. What is the percent of change for the volume of air inside the balloon? 43) You put $ in a simple interest savings account. Two years later, the total account balance is $ Part A: How much interest did you earn? Part B: What is the interest rate of the savings account? Show your work. Part C: What will be the total amount of money in the account after 8 years? Show your work. 5

6 44) A pair of jeans costs $48 dollars. The jeans were marked down to $30. Part A: Show how to find the percent decrease of the price. Round to the nearest whole percent. Part B: A customer comes in with a coupon for 15% off a pair of jeans. They can either use the coupon on the full price or get the discount price without the coupon. Which is the better deal? 45) Jacob is buying lunch at a diner. His lunch costs $7.50 plus a 16% tip. Part A: How much does his lunch cost? Part B: The total cost of his lunch is 4% of his paycheck for the week. How much is Jacob s paycheck? 46) Lee has earned 51 points on his latest math quiz. Part A: If his grade was an 85% on the quiz, how many points was the quiz out of? Part B: Lee s friend William eared 75% on the same quiz. How many points did he earn? Writing Answer the following questions in complete sentences. Be sure to use examples and correct math terminology when possible. 1) Describe a real life situation where a percent of change would be used. Explain WHY it would be a percent of change. 6