Reteach. Teacher Edition. Chapter 11. Grade 4

Transcription

1 Reteach Teacher Edition Chapter 11 Grade 4

2 Lesson 1 Reteach Customary Units of Length The table below shows the different customary units of length and the tools used to measure each unit. Customary Units Unit Example Tool inch ruler foot 1 1 ft yardstick or ruler yard yardstick 1 yd List an item that would be about the same length as each measurement given. Sample answers given inches human hand height of ceiling feet eraser 3. 1 inch 4. 2 yards teacher s board What customary inches unit would you use to measure the following? 5. insect 6. playground inches 7. pencil 8. soccer field feet or yards feet or yards Grade 4 Chapter 11 Customary Measurement 87

3 Lesson 2 Reteach Convert Customary Units of Length Amil ran 50 yards Friday night in the football game. How many feet did he run? Find the conversion rate between yards and feet. 1 yard = 3 feet Convert 50 yards to feet. To perform the conversion, multiply by yards = 150 feet Complete ft = ft = ft = ft = yards = 120 feet ft = yards = 144 inches Explain how you found your answer. Sample answer: I multiplied 4 yards by 3 to get 12 feet then I multiplied 12 by 12 inches to get 144 inches 6. 3 yards = 108 inches yards = 192 ft ft = 72 inches Explain how you found your answer. Sample answer: I know that there are 12 inches in one foot, so I multiplied 6 feet by 12 inches to get 72 inches. 88 Grade 4 Chapter 11 Customary Measurement

4 Lesson 3 Reteach Customary Units of Capacity Capacity is the amount of liquid a container can hold. The table lists five customary units of capacity in order from smallest to largest. It also lists a container that is a good estimate for each unit. Unit fluid ounce cup pint quart gallon Estimate two spoons cocoa mug milk carton from school lunch dog bowl large milk jug Choose the most reasonable estimate for the capacity of a glass of milk. A. 1 fluid ounce C. 1 quart B. 1 cup D. 1 gallon Look at the chart. Which unit is closest to the capacity of a glass of milk? cup A glass of milk holds more than 1 fluid ounce but less than 1 quart. So, the correct answer is B. Circle the most reasonable estimate. 1. A. 8 fluid ounces B. 8 pints C. 8 quarts D. 8 gallons 2. F. 1 cup G. 1 pint H. 1 quart I. 1 gallon Grade 4 Chapter 11 Customary Measurement 89

5 Lesson 4 Reteach Convert Customary Units of Capacity You can convert, or change, from one unit of capacity to another. Look at the exercise below. You can use the four-step plan to help you solve this exercise. 7 pt = c 1 c = 8 fl oz 2 c = 1 pt 2 pt = 1 qt 4 qt = 1 gal Understand Plan Solve Check You must convert 7 pints to cups. To convert from a bigger unit to a smaller unit you will need to multiply. There are 2 cups in a pint, so multiply by = 14 c There are 14 cups in 7 pints. To check, convert from cups to pints = 7 Complete each conversion c = fl oz 2. 1 gal = pt gal = qt 4. 3 pints = fluid ounces qt = pt 6. 2 gallons = cups gallons = quarts 8. 2 qt = fl oz Grade 4 Chapter 11 Customary Measurement

6 Lesson 5 Reteach Customary Units of Weight An object s heaviness is called its weight. There are three customary units of weight: ounces, pounds, and tons. The number line below shows the units from lightest to heaviest. It also shows objects that are close estimates for each unit. ounce pound ton Which is the most reasonable unit measurement for the weight of the computer? Look at your number line. Where would the computer go on the number line? The computer s weight is more than the soup s weight but less than the bus s weight. So, pounds are the most reasonable unit. Choose the most reasonable estimate for the weight of each object A. 3 ounces B. 3 pounds C. 30 pounds D. 3 tons 1. A F. 1 ounce G. 1 pound H. 1 ton I. 100 tons 2. H Grade 4 Chapter 11 Customary Measurement 91

7 Lesson 6 Reteach Convert Customary Units of Weight You can convert, or change, from one unit of weight to another. Look at the exercise below. You can use the four-step plan to help you solve this exercise. 1 pound (lb) = 16 ounces (oz) 1 ton (T) = 2,000 pounds (lb) Find how many ounces are equal to 6 pounds. 6 lb = oz Understand Plan You must convert 6 pounds to ounces. You are going from a bigger unit to a smaller unit. So, multiply. There are 16 ounces in a pound, so multiply by 16. Solve Check Complete each conversion = 96 oz There are 96 ounces in 6 pounds To check, convert from ounces to pounds = lb = oz 2. 1 T = oz 48 32, T = lb pounds = ounces 6, lb = oz 6. 2 T = lb 128 4, T = lb 8. 3 T = oz 10,000 96, Grade 4 Chapter 11 Customary Measurement

8 Lesson 7 Reteach Convert Units of Time You can convert, or change, from one unit of time to another. These are common units of time: 1 minute (min) = 60 seconds (s) 1 hour (h) = 60 min 1 day (d) = 24 h 1 week (wk) = 7 d 1 year (y) = 52 wk = 12 months (mo) How many days are in 6 weeks? Use the chart above and the four-step plan to solve. Understand Plan You must convert weeks to days. You are going from a bigger unit to a smaller unit. So, multiply. Weeks are bigger than days, so multiply by 7. Solve 6 7 days = 42 days There are 42 days in 6 weeks. Check To check, convert from days to weeks = 6 Complete each conversion hours = minutes 2. 5 years = weeks days = hours 4. 7 years = months hours = minutes minutes = seconds Grade 4 Chapter 11 Customary Measurement 93

9 Lesson 8 Reteach Display Measurement Data in a Line Plot A line plot is a type of graphic organizer that shows data on a number line. Line plots are used to show frequency in data, or how many times a certain number appears. You can record information from a tally chart on a line plot. A line plot makes it easy to see which values occur most often. Sandwich Weight 1 lb 4 1 lb 2 3 lb 4 1 lb lb 1 lb 4 2 lb 4 lb Without even counting, you can see by the height of the s on the line plot that the most common sandwich weight is 1_ 2 pound. Record the data from the tally chart on the line plot. Make an for each tally mark in the chart. 1. Bolt Size () Yogurt Serving Size (C) 1 c 3 2 c 3 1 c c c 1 c Grade 4 Chapter 11 Customary Measurement

10 Lesson 9 Reteach Solve Measurement Problems Sometimes, you need to solve measurement problems by converting, or changing units. Kent drinks 8 cups of orange juice each week. How many fluid ounces of orange juice will he drink in 2 weeks? 1 Choose an operation. You know how much orange juice Kent drinks in 1 week. You want to know how much he drinks in 2 weeks. So, you will multiply. 2 Perform the operation. 8 c 2 = 16 c 3 Convert the units. The problem asks how many fluid ounces of orange juice Kent drinks in 2 weeks. You need to convert cups to fluid ounces. A cup is larger than a fluid ounce, so you will multiply. There are 8 fluid ounces in 1 cup; multiply by c 8 = 128 fl oz So, Kent will drink 128 fl oz of orange juice in 2 weeks. Solve. 1. Belinda read her book for 1 hour on Monday and 2 hours on Tuesday. How many minutes did Belinda spend reading her book in all? Add: 1 hour and 2 hours = 3 hours; Multiply: 3 hours 60 = 180 minutes. 2. Edgar threw a paper airplane 4 yards. Shelli threw a paper airplane 3 feet farther. How many feet did Shelli s airplane travel? Multiply: 4 yards 3 feet = 12 feet. Add: 12 feet + 3 feet = 15 feet. Grade 4 Chapter 11 Customary Measurement 95

11 Lesson 10 Reteach Problem Solving: Guess, Check, and Revise Meng rides the bus with 14 other students. One-fifth of the students live on Birch Street. The rest of the students live on Maple Street or Hickory Street. Two more students live on Maple Street than live on Hickory Street. How many live on Hickory Street? Step 1 Understand What facts do you know? 15 students ride the bus. 1_ of the students live on Birch Street. 5 Two more students live on Maple Street than live on Hickory Street. What do you need to find? I need to find the number of students who live on Hickory Street. Step 2 Plan Make a plan. I will guess, check, and revise to solve the problem. Step 3 Solve Step 4 Check Carry out your plan. First, I will subtract the number of students who live on Birch Street. One-fifth of 15 is = 12 Now I need to think of numbers with a sum of 12 and a difference of 2. Try this: = 12 Revise: = 12 Revise: = 12 So, 5 students live on Hickory Street. Make sure your answer is reasonable. These cannot be correct because the difference is not 2. This is correct. The sum is 12, and the difference is 2. Reread the problem to make sure the answer fits. The answer makes sense with the information given. So the answer is reasonable. 96 Grade 4 Chapter 11 Customary Measurement

12 Lesson 10 Reteach Guess, check, and revise to solve each problem. Problem Solving: Guess, Check, and Revise (continued) 1. Donice volunteers at animal shelter for 2 hours. She spends three times as long cleaning kennels as she does walking dogs. How many minutes does she spend on each task? 90 minutes cleaning kennels and 30 minutes walking dogs 2. For a craft project, Miguel needs a board that is 1 foot long. He has a board that is 16 inches long. How many inches does Miguel need to trim off the end? He needs to trim 4 inches. 3. There is 1 gallon of milk shared among 8 friends. If each friend gets the same amount, how many cups of milk do they each get? 2 cups Grade 4 Chapter 11 Customary Measurement 97