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STUDY LINK 12 1 Examples of Rates 339 47 Name Date Time Copyright © Wright Group/McGraw-Hill 1. Look for examples of rates in newspapers, in magazines, and on labels. Study the two examples below, and then list some of the examples you find. If possible, bring your samples to class. Example: says “Servings Per Container 3 1 2” Example: The package doesn’t say so, but there a re always 4 bulbs in each package. Example: Example: Example: Label on a can of corn Lightbulbs come in packages of 4 bulbs. 2. 4 5 1 5 3.  7 8 3 4 Practice Amount Per Serving Serving Size 110 g Servings Per Container 3 1/2 4.  1 9 8 9 5. 1 3 3 6

LESSON 12 1 Name Date Time Median and Mean 340 Copyright © Wright Group/McGraw-Hill Copyright © Wright Group/McGraw-Hill Anthony’s first 4 test scores for his weekly 20-word spelling tests were 80%, 90%, 100%, and 75%. 1. What is Anthony’s medianscore? % 2. What score must Anthony get on his next test to maintain his median score? % Explain your answer. 3. Anthony would like to raise his meanscore to 90% or higher. If he takes one more spelling test, can he do it? Explain your answer. 73 75 LESSON 12 1 Name Date Time Median and Mean Anthony’s first 4 test scores for his weekly 20-word spelling tests were 80%, 90%, 100%, and 75%. 1. What is Anthony’s medianscore? % 2. What score must Anthony get on his next test to maintain his median score? % Explain your answer. 3. Anthony would like to raise his meanscore to 90% or higher. If he takes one more spelling test, can he do it? Explain your answer. 73 75

STUDY LINK 12 2 Rates 341 Name Date Time Copyright © Wright Group/McGraw-Hill Solve the problems. 1. Hotels R Us charges $45 per night for a single room. At that rate, how much does a single room cost per week?$ 2. The Morales family spends about $84 each week for food. On average, how much do they spend per day? $ 3. Sharon practices playing the piano the same amount of time each day. She practiced a total of 4 hours on Monday and Tuesday combined. At that rate, how many hours would she practice in a week?hours 4. People in the United States spend an average of 6 hours and 4 minutes each week reading newspapers. a. That’s how many minutes per week?minutes per week b. At that rate, how much time does an average person spend reading newspapers in a 3-day period? minutes Try This Practice 5. 24 º 379 6. 870 º 63  7. 652 8  8. 546 42  Hours Days 1234567 Minutes Days 1234567 175 176

STUDY LINK 12 3 Mammal Rates Copyright © Wright Group/McGraw-Hill 342 Name Date Time 1. A mole can dig a tunnel 300 feet long in one night. How far could a mole dig in one week? About feet 2. An elephant may eat 500 pounds of hay and drink 60 gallons of water in one day. a. About how many pounds of hay could an elephant eat per week? About pounds b. About how many gallons of water could an elephant drink per week? About gallons 3. The bottle-nosed whale can dive to a depth of 3,000 feet in 2 minutes. About how many feet is that per second? About feet per second 4. A good milking cow will give up to 1,500 gallons of milk in a year. a. About how many gallons is that in 3 months? About gallons b. About how many quartsis that in 3 months? About quarts Try This 5. Sloths spend up to 80 percent of their lives sleeping. Not only is a sloth extremely sleepy, but it is also very slow. A sloth travels on the ground at a speed of about 7 feet per minute. In the trees, its speed is about 15 feet per minute. a. After one hour, how much farther would a sloth have traveled in the trees than on the ground (if it didn’t stop to sleep)? About feet b. About how long would it take a sloth to travel 1 mile on the ground? (Hint:There are 5,280 feet in a mile.)About minutes, or hours 6. 59 º 27  7. 648 º 85 8. 904 5  9. 536 / 8 Practice 47

LESSON 12 3 Name Date Time Mammal 100-Yard Dash 343 Copyright © Wright Group/McGraw-Hill It could not happen, of course, but suppose that you, an elephant, and a cheetah were to race a distance of 100 yards, or 300 feet. Which of you would win? Which would come in second? Third? 1. My Prediction: First Second Third 2. On the diagram below, show the winner crossing the finish line. Estimate where you think the second-place and third-place mammals would be when the fastest mammal wins. Write “C” for the cheetah, “E” for the elephant, and “Me” for yourself. 3. What information would help you predict the winner? 4. Complete the table below by using the “last race results” to find each mammal’s top sprint speed in feet per second. 0 30 60 90120 150 180 210 240 270 300 feet Start Finish Mammal Last Race ResultsTop Sprint Speed (approximate) Fourth Grader 84 yards in 12 seconds ft /sec Cheetah 2,448 inches in 2 seconds ft /sec Elephant 36 yards in 3 seconds ft /sec 47

LESSON 12 3 Name Date Time Mammal 100-Yard Dash continued 344 Copyright © Wright Group/McGraw-Hill 5. According to the ft/sec rates, how would the 300-foot race among an elephant, a cheetah, and a fourth grader turn out? First Second Third 6. About how long would it take for the winner of the race to run 300 feet? About seconds 7. By the time the winner crosses the finish line, how far would the other mammals have run? Second-place mammal About feet Third-place mammal About feet 8. Would it be a close race? 9. On the diagram below, show which mammal will win the race and where the other two mammals will be when the winner crosses the finish line. 10. About how many times faster is the first-place mammal than a. the second-place mammal? b. the third-place mammal? 11. The top sprint speed for a squirrel is 18 feet per second. Does this mean that you could catch a squirrel by running after it? Explain. 0 30 60 90120 150 180 210 240 270 300 feet Start Finish

STUDY LINK 12 4 Unit Prices 345 Name Date Time Copyright © Wright Group/McGraw-Hill Solve the unit price problems below. Complete the tables if it is helpful to do so. 1. A 12-oz bag of pretzels costs 96 cents. The unit price is per ounce. Dollars 0.96 Ounces 13912 Dollars 1.40 Liters 1234 Dollars 2.07 Rolls 123 2. A package of 3 rolls of paper towels costs $2.07. The unit price is per roll. 3. A 4-liter bottle of water costs $1.40. The unit price is per liter. 4. Choose 4 items from newspaper ads. In the table below, record the name, price, and quantity of each item. Leave the Unit Price column blank. Item Quantity Price Unit Price Golden S u n 24 ounces $2.99 Raisin s Practice Name the factor pairs for each number. 5. 12 6. 50 47

LESSON 12 4 Name Date Time Stock-Up Sale 346 Copyright © Wright Group/McGraw-Hill Party Town is having a summer stock-up sale. The ad below shows the original price of each item and the sale price if you buy a certain number of items. Use bills and coins to help you find the stock-up price per item. Party Music CDs $8.00each 1. You pay per CD. $5.00 Stock-Up Price: Buy 5 for $25.00. String in a Can $3.00each 2. You pay per can. Stock-Up Price: Buy 8 for $16.00. 3. Stock-Up Price: Buy 12 for $14.40. 4. Stock-Up Price: Buy 3 for $29.97. Glow bracelets $2.50each 5. Stock-Up Price: Buy 6 for $10.50. Party Hats $9.99for a package of 45 6. Stock-Up Price: Buy 4 packages for $19.96. Mylar Balloon $1.99each Piñata $14.99each You pay per balloon. You pay per bracelet. You pay per piñata. You pay per package.

STUDY LINK 12 5 Unit Pricing 347 47 Name Date Time Copyright © Wright Group/McGraw-Hill 1. A package of 3 muffins costs $1.89. What is the price per muffin? 2. A 5-pound bag of rice costs $1.85. What is the price per pound? 3. Chewy worms are sold at $2.40 per pound. What is the price per ounce? 4. A 6-pack of bagels costs $2 .11. What is the price per bagel? 5. A 2-pound bag of frozen corn costs $2.03. What is the price per pound? 6. A store sells yogurt in two sizes: The 8-ounce cup costs 72 cents, and the 6-ounce cup costs 60 cents. Which is the better buy? Explain your answer. 7. Make up your own “better buy” problem. Then solve it. Practice Name all the factors. 8. 42 9. 23

LESSON 12 5 Name Date Time Which is the Better Buy? 348 Copyright © Wright Group/McGraw-Hill For each problem, draw pictures and use bills and coins to decide which product is the better buy. 1. A 12-oz bottle of sports drink costs $0.75. A six-pack of 12-oz sports drink costs $3.60. Which is the better buy? Explain how you know. 2. One pencil costs $0.10. A box of 12 pencils costs $1.80. Which is the better buy? Explain how you know. 3. A cup of yogurt costs $0.90. A four-pack of yogurt costs $3.00. Which is the better buy? Explain how you know. 4. Write and solve your own “better buy” problem.

LESSON 12 5 Name Date Time Measuring Air Pressure with a Barometer 349 Copyright © Wright Group/McGraw-Hill Some people think that air does not weigh anything. But it does—you can prove this by doing a simple experiment. Weigh a deflated soccer ball or basketball. Next, pump it full of air. Weigh it again. The ball will weigh more after you have pumped air into it. This shows that the air you pumped in does have weight. In 1643, Evangelista Torricelli, a student of Galileo, invented an instrument for measuring air pressure—how much the weight of air pushes on a surface. He made a glass tube about 3 1 2feet long, closed it at one end, and filled it with mercury. Then he turned the tube upside down and put it into an open container that held more mercury. When he did that, the mercury in the tube fell a few inches and then stopped. You may wonder why some of the mercury remained in the tube. Why didn’t allthe mercury flow out of the tube and mix with the mercury in the container? The reason is that the air above the open container pushes down on the mercury. This, in turn, supports the mercury in the tube. The greater the air pressure, the higher the level of the mercury in the tube. The instrument Torricelli invented is called a mercury barometer. The height of the mercury in the tube depends on the barometric pressure. When a weather forecaster reports that the barometric pressure is 30.25, this means that the mercury in the tube has reached a level of 30.25 inches. Barometers are used to predict the weather. In fact, Torricelli’s barometer came to be known as the “weather glass.” When the weather pattern is changing, the barometric pressure also changes. When the barometer readings fall steadily or suddenly, a storm is probably on its way. The faster the barometer readings fall and the lower the reading, the more severe the storm is likely to be. When the barometer readings rise, you can expect fair weather. An early model mercury barometer

LESSON 12 5 Name Date Time Measuring Air Pressure with a Barometer cont. 350 Copyright © Wright Group/McGraw-Hill Mercury barometers are awkward to carry from one place to another. A more convenient type of barometer is the aneroid barometer. This is the sort of barometer you may have in your school or at home. Aneroidmeans “without liquid.” The units on an aneroid barometer have the same meaning as the units on a mercury barometer. If your aneroid barometer reads 29.85, a mercury barometer would show 29.85 inches of mercury in the tube. Aneroid barometers have two needles. One needle moves when the barometric pressure changes. (It is the needle pointing to 30 in the picture.) The other needle stays in place unless someone moves it. If you move the smaller needle to today’s reading, later you will be able to measure how much the barometric pressure has changed. Barometric pressure is affected by elevation—how high the land is above sea level. The average barometric pressure at sea level is about 30 inches. At higher elevations, the average barometric pressure will be less. The Elevation Rule For every 100 feet you climb, the barometer reading will drop about 0.1 inch.  For every 1,000 feet you climb, the reading will drop about 1 inch. Denver, Colorado, is about 5,000 feet above sea level; the average barometric pressure in Denver is about 25 inches. Here is a map of the island of Hawaii. The numbers on the map give barometer readings for the cities shown—all taken under similar weather conditions. All readings were also taken at the same time. They vary because the cities are at different heights, or elevations, above sea level. Aneroid barometer 5 30 5 31 5 26 5 27 5 28 5 29CHANGE RAIN STORMY FAIR VERY DRY Kau DesertKeaau 29.6 Kilauea Crater Papa 28.4Mauna LoaHilo 30.0 Pohauloa 23.4 Waikii 26.5Wainea 27.0 Hualalai CraterMauna Kea HAWAII Pacific Ocean Numbers below cities are barometer readings.

LESSON 12 5 Name Date Time The Barometer and Elevation 351 Copyright © Wright Group/McGraw-Hill Refer to the map of Hawaii and the Elevation Rule on Math Masters, page 350 to answer the following questions. 1. Hilo is the largest city on the island of Hawaii. It is at sea level. This means that its elevation is 0 feet above sea level. What is the barometer reading in Hilo?About inches 2. Compare Keaau to Wainea. a. What is the barometer reading in Keaau? About inches b. What is the barometer reading in Wainea?About inches c. Which is higher above sea level: Keaau or Wainea? 3. Compare Waikii to Hilo. a. What is the barometer reading in Waikii?About inches b. How much less is the barometer reading in Waikii than in Hilo? inches less c. What is the elevation of Waikii? About feet above sea level 4. The barometer reading at the top of Kilauea Crater is 1.7 inches less than at the top of Hualalai Crater. a. Which crater has a higher elevation? b. About how much higher is it? About feet 5. The Kau Desert is about 2,500 feet above sea level. What should the barometer reading be there?About inches 6. The highest mountains on Hawaii are Mauna Loa and Mauna Kea. Their heights are nearly the same. If the barometer reads 16.4 inches at the top of these mountains, what is their elevation? About feet above sea level

STUDY LINK 12 6 Country Statistics Copyright © Wright Group/McGraw-Hill 352 Name Date Time 1. China has the longest border in the world —13,759 miles. Russia has the second longest border in the world —12,514 miles. How much shorter is Russia’s border than China’s border? miles 2. The area of Russia is about 1,818,629 square miles. The area of Spain, including offshore islands, is about 194,897 square miles. About how many times larger is Russia than Spain? times larger 3. Students in China attend school about 251 days per year. Students in the United States attend school about 180 days per year. a. About what percent of the year do Chinese students spend in school? % b. About what percent of the year do American students spend in school? % 4. English is officially spoken in 54 countries. Portuguese is officially spoken in 8 countries. Portuguese is spoken in about what fraction of the number of English-speaking countries? 5. The table to the right shows the countries in the world with the most neighboring countries. Use the data in the table to answer the following questions. a. Which country has the maximum number of neighbors? b. What is the range? c. What is the mode? d. What is the median? Country Number of Neighbors Brazil 10 China 15 Dem. Rep. of Congo 9 Germany 9 Russia 14 Sudan 9 175 176

LESSON 12 6 Name Date Time Interpreting the Remainder 353 Copyright © Wright Group/McGraw-Hill Draw a picture to illustrate the problem. Then solve the problem. 1. The roller coaster holds 24 people per ride. There are 65 people waiting in line. How many times does the roller coaster need to run before everyone in line gets a turn to ride? Number model: Answer: times What did you do about the remainder? Circle the answer. Ignored it. Reported it as a fraction or decimal. Rounded the answer up. Why? 2. Cedric’s teacher is ordering pizza for an end-of-year party. He has $35.00 to spend. A large cheese pizza costs $8.00. How many pizzas can he order? Number model: Answer: pizzas What did you do about the remainder? Circle the answer. Ignored it. Reported it as a fraction or decimal. Rounded the answer up. Why? Picture: Picture:

STUDY LINK 12 7 Family Letter Copyright © Wright Group/McGraw-Hill 354 Name Date Time Congratulations! By completing Fourth Grade Everyday Mathematics,your child has accomplished a great deal. Thank you for all of your support. This Family Letter is a resource to use throughout your child’s vacation. It includes an extended list of Do-Anytime Activities, directions for games that can be played at home, a list of mathematics-related books to check out over vacation, and a sneak preview of what your child will be learning in Fifth Grade Everyday Mathematics.Enjoy the vacation! Do-Anytime Activities Mathematics means more when it is rooted in real-life situations. To help your child review many of the concepts he or she has learned in fourth grade, we suggest the following activities for you and your child to do together over vacation. These activities will help your child build on the skills he or she has learned this year and help prepare him or her for Fifth Grade Everyday Mathematics. 1.Have your child practice any multiplication and division facts that he or she has not yet mastered. Include some quick drills. 2.Provide items for your child to measure. Have your child use personal references, as well as U.S. customary and metric measuring tools. 3.Use newspapers and magazines as sources of numbers, graphs, and tables that your child may read and discuss. 4.Have your child practice multidigit multiplication and division using the algorithms that he or she is most comfortable with. 5.Ask your child to look at advertisements and find the sale prices of items using the original prices and rates of discount or find rates of discount using original prices and sale prices. Have your child use a calculator and calculate unit prices to determine best or better buys. 6.Continue the World Tour by reading about other countries. Everyday M athem atics

355 Copyright © Wright Group/McGraw-Hill Building Skills through Games The following section lists rules for games that can be played at home. You will need a deck of number cards, which can be made from index cards or by modifying a regular deck of cards as follows: A regular deck of playing cards includes 54 cards (52 regular cards plus 2 jokers). Use a permanent marker to mark some of the cards: Mark each of the four aces with the number 1. Mark each of the four queens with the number 0. Mark the four jacks and four kings with the numbers 11 through 18. Mark the two jokers with the numbers 19 and 20. Beat the Calculator Materials number cards 1–10 (4 of each); calculator Players 3 Directions 1.One player is the “Caller,” one is the “Calculator,” and one is the “Brain.” 2.Shuffle the deck of cards and place it facedown. 3.The Caller draws two cards from the number deck and asks for their product. 4.The Calculator solves the problem with a calculator. The Brain solves it without a calculator. The Caller decides who got the answer first. 5.The Caller continues to draw two cards at a time from the number deck and asks for their product. 6.Players trade roles every 10 turns or so. Example: The Caller draws a 10 and 7 and calls out “10 times 7.” The Brain and the Calculator solve the problem. The Caller decides who got the answer first. Variation 1:To practice extended multiplication facts, have the Caller draw two cards from the number deck and attach a 0 to either one of the factors or to both factors before asking for the product. Example: If the Caller turns over a 4 and a 6, he or she may make up any one of the following problems: 4 60 40 6 40 60 Variation 2:Use a full set of number cards: 4 each of the numbers 1–10, and 1 each of the numbers 11– 20. Family Letter cont. STUDY LINK 12 7 Name Date Time 7 7 10 10 4 4 6 6

Copyright © Wright Group/McGraw-Hill 356 Building Skills through Games Name That Number Materials 1 complete deck of number cards Players 2 or 3 Object of the game To collect the most cards Directions 1.Shuffle the cards and deal five cards to each player. Place the remaining cards number-side down. Turn over the top card and place it beside the deck. This is the target numberfor the round. 2.Players try to match the target number by adding, subtracting, multiplying, or dividing the numbers on as many of their cards as possible. A card may be used only once. 3.Players write their solutions on a sheet of paper or a slate. When players have written their best solutions: They set aside the cards they used to name the target number. Replace them by drawing new cards from the top of the deck. Put the old target number on the bottom of the deck. Turn over a new target number, and play another hand. 4.Play continues until there are not enough cards left to replace all of the players’ cards. The player who sets aside more cards wins the game. Example: Target number: 16 A player’s cards: Some possible solutions: 10 8 2 16 (three cards used) 7 2 10 8 16 (four cards used) 8 / 2 10 7 5 16 (all five cards used) The player sets aside the cards used to make a solution and draws the same number of cards from the top of the deck. 2 2 5 5 7 7 8 8 10 10 Family Letter cont. STUDY LINK 12 7 Name Date Time

357 Copyright © Wright Group/McGraw-Hill Vacation Reading with a Mathematical Twist Books can contribute to children’s learning by presenting mathematics in a combination of real-world and imaginary contexts. The titles listed below were recommended by teachers who use Everyday Mathematicsin their classrooms. They are organized by mathematical topic. Visit your local library and check out these mathematics-related books with your child. Geometry A Cloak for the Dreamerby Aileen Friedman The Greedy Triangleby Marilyn Burns Measurement The Magic School Bus Inside the Earth by Joanna Cole The Hundred Penny Boxby Sharon Bell Mathis Numeration Alexander, Who Used to be Rich Last Sundayby Judith Viorst If You Made a Million by David M. Schwartz Fraction Actionby Loreen Leedy How Much Is a Million?by David M. SchwartzOperations Anno’s Mysterious Multiplying Jar by Masaichiro Anno The King’s Chessboard by David Birch One Hundred Hungry Ants by Elinor J. Pinczes A Remainder of Oneby Elinor J. Pinczes Patterns, Functions, and Sequences Eight Hands Round by Ann Whitford Paul Visual Magicby David Thomas Reference Frames The Magic School Bus: Inside the Human Bodyby Joanna Cole Pigs on a Blanket by Amy Axelrod Looking Ahead: Fifth Grade Everyday Mathematics Next year your child will . . . Develop skills with decimals and percents Continue to practice multiplication and division skills, including operations with decimals Investigate methods for solving problems using mathematics in everyday situations Work with number lines, times, dates, and rates Collect, organize, describe, and interpret numerical data Further explore the properties, relationships, and measurement of 2- and 3-dimensional objects Read, write, and use whole numbers, fractions, decimals, percents, negative numbers, and exponential notation Explore scientific notation Again, thank you for all of your support this year. Have fun continuing your child’s mathematical experiences throughout the vacation! Family Letter cont. STUDY LINK 12 7 Name Date Time