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Find each perimeter. Then find each area in square units.
Discovering Math, Measurement, Tools for Measurement...or, It’s Instrumental
Name Date
LEVEL
3
The appropriate tool should be used to make a measurement. For example:
Length: rulers, yardsticks, tape measures, meter sticksUse rulers for shorter lengths and yardsticks or tape measures for longer lengths.Units of length include inches, feet, yards, centimeters, and meters.
Volume: measuring spoons, measuring cups, gallon containersUnits of volume include cups, gallons, and liters.
AngleMeasure: protractors
An angle opening is measured in degrees.
Weightor Mass: scales, balances
Units of weight include ounces or pounds. Units of mass include grams or kilograms.
Choose the best tool to measure each item. Write ruler, yardstick, tape measure, meter stick, gallon container, measuring cup, measuringspoon, protractor, scale, or balance.
1. an angle of 30°
[protractor]
2. the length of a caterpillar
[ruler]
What does each measurement measure? Write length, volume, angle measure, mass, or weight. Then write the tool used to make eachmeasurement. Write ruler, measuring cup, protractor, scale, or balance.
Discovering Math, Measurement, Sizes of Standard Units...or, It’s the One
Name Date
SIZES OF STANDARD UNITS
1. 2 lb � oz [32]
4. 2 pt � c [4]
7. 10 ft � in. [120]
10. 8 pt � qt [4]
2. 3 qt � pt [6]
5. 4 gal � qt [16]
8. 6 c � pt [3]
11. 8 c � qt [2]
3. 4 ft � in. [48]
6. 5 lb � oz [80]
9. 8 qt � gal [2]
12. 5 qt � c [20]
CHALLENGE
A melon weighs 2 pounds 5 ounces. Another melon weighs 2 pounds 8ounces. How many ounces do the two melons weigh in all?
[77 oz]
LEVEL
1
Multiply by smaller units per larger unit to convert from a larger unit to a smaller unit. The measurement becomes a greater number of smaller units.Divide by smaller units per larger units to convert from a smaller unit to a larger unit. The measurement becomes a lesser number of larger units
Discovering Math, Measurement, Sizes of Standard Units...or, It’s the One
Name Date
LEVEL
2
SIZES OF STANDARD UNITS
1. 48 in. � ft [4]
4. 8 lb � oz [128]
7. 12 qt � gal [3]
2. 32 oz � lb [2]
5. 8 ft � in. [96]
8. 120 in. � ft [10]
3. 6 gal � qt [24]
6. 5 qt � pt [10]
9. 80 oz � lb [5]
10. 2 lb 5 oz � oz [37]
12. 6 qt 1 pt � pt [13]
11. 4 ft 9 in. � in. [57]
13. 3 gal 2 qt � qt [14]
Use equivalent measures to convert standard units.To change from a larger unit to a smaller unit, multiply by smaller units per larger unit.The measurement becomes a greater number of smaller units. To change from a smaller unit to a larger unit, divide by smaller units per larger unit. The measurement becomes a lesser number of larger units.
Length12 inches (in.) � 1 foot (ft)
6 ft 5 in. � ? in. Think: A foot is a larger unit than an inch.
Multiply to convert 6 ft to inches: 6 ft � 12�inft.
�� 72 in.
Add to find the total: 6 ft 5 in. � 72 in. � 5 in. � 77 in.
Weight16 ounces (oz) � 1 pound (lb)
48 oz � ? lb Think: An ounce is a smaller unit than a pound.There are many ounces in a pound, thus fewer pounds than ounces in the same weight.
Discovering Math, Measurement, Sizes of Standard Units...or, It’s the One
Name Date
Use equivalent measures to convert standard units.Multiply by smaller units per larger unit to convert from a larger unit to a smaller unit. The measurrement becomes a greater number of smaller units.Divide by smaller units per larger unit to convert from a smaller unit to a larger unit. The measurement becomes a lesser number of larger units.
Write each missing number.
Length12 inches (in.) � 1 foot (ft)
3 ft � 1 yard (yd)
40 in. � ? ft 40 in. � 12
�inft.
�� 3 R4 ft
40 in. � 3 ft 4 in.
Weight16 ounces (oz) � 1 pound (lb)
3 �12� lb � ? oz
3 �12� lb � 16
�olbz�
� �72� lb � 16
�olbz�
= 56 oz
3 �12� lb � 56 oz
1. 2 �12� ft � in. [30]
4. 3 �14� ft � in. [39]
2. 1 �34� lb � oz
5. 2 �34� qt � c [11]
3. 2 gal � c [32]
6. 72 in. � yd [2]
Liquid Volume1 pint (pt) � 2 cups (c) Sometimes, more than one 1 quart (qt) � 4 cups (c) conversion is needed.1 quart (qt) � 2 pints (pt) 3 gal � ? cups1 gallon (gal) � 4 qt 3 gal � 3 gal � 4
�gqatl
�� 12 qt
3 gal � 12 qt � 4�qct
�� 48 c
[28]
LEVEL
3
7. 35 in. � ft in. [2] [11]
9. 60 oz � lb oz [3] [12]
11. 20 ft � yd ft [6] [2]
13. 62 in. � ft in. [5] [2]
8. 14 qt � gal qt [3] [2]
10. 57 in. � ft in. [4] [9]
12. 85 oz � lb oz [5] [5]
14. 15 c � qt c[3] [3]
Figures with the same perimeter can have different areas.
Find the perimeter and area of each figure. Which figure in each group has the greatest area?
Discovering Math, Measurement, Areas and Perimeters...or, In and Around
Name Date
LEVEL
2
AREAS AND PERIMETERS
Figures with the same perimeter can have different areas.
Perimeter of Rectangle A Perimeter of Rectangle B Perimeter of Square CP = 12 + 4 + 12 + 4 = 32 P = 10 + 6 + 10 + 6 = 32 P = 8 + 8 + 8 + 8 = 32Perimeter = 32 cm Perimeter = 32 cm Perimeter = 32 cm
Area of Rectangle A Area of Rectangle B Area of Square CA = l � w = 12 � 4 = 48 A = l � w = 10 � 6 = 60 A = l � w = 8 � 8 = 64Area = 48 sq cm Area = 60 sq cm Area = 64 sq cm
As the sides of the rectangles get closer in length, the area increases but the perimeter does not change.
The perimeters are all the same for the rectangles within a group.Predict the figure in each group that will have the greatest area. Then find the perimeter and area of each figure.
Discovering Math, Measurement, Areas and Perimeters...or, In and Around
Name Date
When the lengths of sides of a figure are doubled, keeping the figure the same shape, theperimeter is doubled, but the area is increased by 4 times.
Perimeter of Rectangle A Perimeter of Rectangle BP = 6 + 4 + 6 + 4 = 20 P = 12 + 8 + 12 + 8 = 40Perimeter = 20 cm Perimeter = 40 cm
As the lengths of the sides are doubled, the perimeter doubles.
Area of Rectangle A Area of Rectangle BA = l � w = 6 � 4 = 24 A = l � w = 12 � 8 = 96Area = 24 sq cm Area = 96 sq cm
As the lengths of the sides are doubled, the area is multiplied by 4.
Find the perimeter and area of each figure. Then double the length and width of each figure.Predict the new perimeter and area. Then check the new perimeter and area.
Discovering Math, Measurement, Variability in Measurement...or, Close Encounters
Name Date
LEVEL
2
VARIABILITY IN MEASUREMENT
Using a customary ruler marked in inches and eighths of inches, you can measure reliablyto the nearest �
18�-inch. The smaller the unit of measurement, the more precise the measurement
can be. If the ruler is accurate, smaller divisions allow reliable measurement closer to thetrue value, which are therefore more accurate measurements.
To make an accurate measurement, align the left edge of the item being measured with the left edge or “0” mark on the ruler.
To the nearest �12�-inch, the string is 1�
12� inches long.
To the nearest �14�-inch, the string is 1�
34� inches long.
To the nearest �18�-inch, the string is 1�
58� inches long.
The measurement of 1�58� inches is the most precise, to the nearest �
18� –inch, and the most
accurate since it uses the smallest unit, so it’s closest to the true value.
Which measurement is the most accurate? Explain why.
1.
[2�18� in. is more accurate since the left end of the straw is aligned with the left end of the ruler,
so the recorded length is closer to the true value. The other straw is not aligned at the end.]
2. A scale in the produce section of a grocery store measures weight inpounds, with no smaller intervals. When Jill puts a melon on the scale, it shows the weight to the nearest marking as 2 pounds. When the clerkputs the same melon on a scale at the register, the measurement is 2pounds 5 ounces. Both scales read “0” when nothing is on the scales.Assuming both scales are accurate, which measurement is more accurate?
[The scale at the register is more accurate since it shows smaller units, so its
Discovering Math, Measurement, Variability in Measurement...or, Close Encounters
Name Date
LEVEL
3
The precision and accuracy of a measurement may depend upon the units of measurement used. A length measured to the nearest �
18�-inch
is more precise than a length measured to the nearest inch, since �18�-inch is a smaller unit. If the ruler is accurate, the measurement will usually also be more accurate, because it will be closer to the true value, within �
18� inch
rather than only within a greater interval.
The accuracy of a measurement may depend upon the tool used to measure. A scale that is set at “0” when it is empty is usually more accurate than a scale that is not set at “0.”
Which measurement is the most accurate? Explain why.
1. Lonnie measures a string using a ruler. He says the string is 4�136� inches
long. Randy measures the same string using a different ruler. He saysthe string is 4�
14� inches long. Both friends align the end of the string with
the left ends of their rulers and measure to the nearest marking. Whosemeasurement is more accurate?
[Lonnie’s because he uses the smaller unit, so his measurement is therefore closer to the true value,
to the closest �116� inch rather than only to the closest �
14� inch.]
CHALLENGE
Which measurement is more accurate? Explain.
[1�12� in., because the reported length happens to be closer to the true value.]
With which ruler could you generally make measurements precise to within acloser interval?
[The second, because the intervals are smaller, so you could repeat
Discovering Math, Measurement, Estimation Strategy... or, How About It?
LEVEL
1
Name Date
ESTIMATION STRATEGIES
You can estimate to help you make decisions about money.
Kendra has $8.00 to spend at the book store. She wants to buy a book that costs $4.95 and a magazine that costs $3.19. Does she have enough money to buy both items?
Round each amount to estimate the total.
The book costs about $5.00.The magazine costs about $3.20.$5.00 � $3.20 � $8.20
Compare the total with the amount she has.
$8.20 � $8.00
$8.20 is more than the amount Kendra has. She does not have enough money to buy both items.
Use an estimate to solve each problem.
1. Enrico has $10.00. He wants to buy some watercolors that cost $7.49and a paint brush that costs $1.99. Does he have enough money to buyboth items? Explain.
[Yes: $7.50 � $2.00 � $9.50 and $9.50 � $10.00]
2. Lourdes has $3.00. She wants to buy 4 different markers that cost$0.69 each. Does she have enough money to buy all the markers?Explain.
[Yes. Each marker costs about $0.70 and $0.70 � 4 � $2.80 and $2.80 � $3.00.]
3. Ryan has $15.00. He wants to buy 2 magazines that cost $4.25 eachand a guidebook that costs $8.79. Does he have enough money to buyall the items? Explain.
Discovering Math, Measurement, Estimation Strategy... or, How About It?
Name Date
LEVEL
2
ESTIMATION STRATEGIES
You can estimate to help you make decisions about money.
Corey is able to save $3.00 each week. He wants to save the money to buy a new game. The game costs $29.95. How many weeks will Corey have to save money before he has enough to buy the game?
Savings each week: $3.00 Cost of game: about $30.00
Divide to find about how many weeks Corey will have to save.
Corey will have to save money for about 10 weeks to buy the game.
Use an estimate to solve each problem.
1. Lara can save $4.00 each month. She wants to save the money to buya new pair of skates that cost $38.50. How many months will Lara haveto save money before she has enough to buy the skates?
[about 10 months]
2. Jason plans to save $3.25 each week to buy a birthday gift for hismother. He wants to buy her a vase that costs $45.00. How manyweeks should Jason plan on saving money to have enough to buy thevase?
[about 15 weeks]
3. Eva is saving $2.25 each week to buy a new book that will cost$13.95. How many weeks will Eva have to save money so that she willhave enough to buy the book?
[about 7 weeks]
103�3�0���3�0�
0
[Estimates may vary. Accept reasonable estimates. Sample estimates are given.]
Discovering Math, Measurement, Estimation Strategy... or, How About It?
Name Date
LEVEL
3
[Estimates may vary. Accept reasonable estimates. Sample estimates are given.]
You can estimate to help you make decisions about money.
Paula and Greg want to earn $2,000 to redecorate a room. Paula works Saturdays at a banquet hall. She earns $75 each time she works. Greg works afternoons at a market. He earns $32 each afternoon he works. Paula will work every Saturday until she earns $800. Greg will work 3 afternoons a week until he earns $1200. How many weeks will each person have to work to meet their goals?
Estimate the number of weeks Paula needs to work.$800 � $80 � 10 Since $75 � $80, adjust the estimate: add 1 more week.
Paula needs to work about 11 weeks.
Estimate the number of weeks Greg needs to work.He earns about $30 � 3, or about $90, each week. $1,200 � $90 ≈ $1,200 � $100 � 12 Since $90 � $100, adjust the estimate: add 1 more week.
Greg needs to work about 13 weeks.
Use an estimate to solve each problem.
1. Marc wants to earn $350 to buy a new printer. He does yard workevery weekend and earns $7.50 each hour he works. He works about 8hours every weekend. How many weekends will Marc have to work tomeet his goal?
[about 6 weekends]
2. Rebecca wants to earn $700 to buy a new computer. She works in acrafts shop twice a week. She works 4 hours each time she works andearns $8.10 each hour she works. How many weeks will Rebecca haveto work to meet her goal?
[about 11 weeks]
Inches, feet, yards, and miles are customary units of length.Centimeters, meters, and kilometers are metric units of length.
Different units are used to measure different lengths.
Choose the unit you would use to measure each length. Write inches, feet, or miles.
Choose the unit you would use to measure each length. Write centimeters, meters, or kilometers.
Discovering Math, Measurement, Selecting Units...or, Sizing It Up
Name Date
LEVEL
2
SELECTING UNITS
Different units of measurement are used to measure different lengths:length of a ladybug: use millimeters.height of a cereal box: use inches or centimeters.length of a football field: use feet, yards, or meters.distance between cities: use miles or kilometers.
Choose the customary unit you would use to measure each length.
Choose the metric unit you would use to measure each length.
Customary Units of Lengthinches, feet, yards, miles
Metric Units of Lengthmillimeters, centimeters, meters, kilometers
Discovering Math, Measurement, Selecting Units...or, Sizing It Up
Name Date
LEVEL
3
Use smaller units to measure lesser lengths and larger units to measure greater lengths. Inches are smaller units than feet. Use inches to measure the width of a car window, but use feet to measure the length of a car.
Use smaller units to measure lesser volumes or capacities and larger units to measure greater volumes or capacities.Gallons are larger units than quarts. Use gallons to measure the amount of gas needed tofuel a car, but use quarts to measure the oil a car uses.
Choose the customary unit you would use to measure each.
Discovering Math, Measurement, Tools for Measurement...or, It’s Instrumental
Name Date
LEVEL
3
The appropriate tool should be used to make a measurement. For example:
Length: rulers, yardsticks, tape measures, meter sticksUse rulers for shorter lengths and yardsticks or tape measures for longer lengths.Units of length include inches, feet, yards, centimeters, and meters.
Volume: measuring spoons, measuring cups, gallon containersUnits of volume include cups, gallons, and liters.
AngleMeasure: protractors
An angle opening is measured in degrees.
Weightor Mass: scales, balances
Units of weight include ounces or pounds. Units of mass include grams or kilograms.
Choose the best tool to measure each item. Write ruler, yardstick, tape measure, meter stick, gallon container, measuring cup, measuringspoon, protractor, scale, or balance.
1. an angle of 30°
[protractor]
2. the length of a caterpillar
[ruler]
What does each measurement measure? Write length, volume, angle measure, mass, or weight. Then write the tool used to make eachmeasurement. Write ruler, measuring cup, protractor, scale, or balance.
Discovering Math, Measurement, Sizes of Standard Units...or, It’s the One
Name Date
SIZES OF STANDARD UNITS
1. 2 lb � oz [32]
4. 2 pt � c [4]
7. 10 ft � in. [120]
10. 8 pt � qt [4]
2. 3 qt � pt [6]
5. 4 gal � qt [16]
8. 6 c � pt [3]
11. 8 c � qt [2]
3. 4 ft � in. [48]
6. 5 lb � oz [80]
9. 8 qt � gal [2]
12. 5 qt � c [20]
CHALLENGE
A melon weighs 2 pounds 5 ounces. Another melon weighs 2 pounds 8ounces. How many ounces do the two melons weigh in all?
[77 oz]
LEVEL
1
Multiply by smaller units per larger unit to convert from a larger unit to a smaller unit. The measurement becomes a greater number of smaller units.Divide by smaller units per larger units to convert from a smaller unit to a larger unit. The measurement becomes a lesser number of larger units
Discovering Math, Measurement, Sizes of Standard Units...or, It’s the One
Name Date
LEVEL
2
SIZES OF STANDARD UNITS
1. 48 in. � ft [4]
4. 8 lb � oz [128]
7. 12 qt � gal [3]
2. 32 oz � lb [2]
5. 8 ft � in. [96]
8. 120 in. � ft [10]
3. 6 gal � qt [24]
6. 5 qt � pt [10]
9. 80 oz � lb [5]
10. 2 lb 5 oz � oz [37]
12. 6 qt 1 pt � pt [13]
11. 4 ft 9 in. � in. [57]
13. 3 gal 2 qt � qt [14]
Use equivalent measures to convert standard units.To change from a larger unit to a smaller unit, multiply by smaller units per larger unit.The measurement becomes a greater number of smaller units. To change from a smaller unit to a larger unit, divide by smaller units per larger unit. The measurement becomes a lesser number of larger units.
Length12 inches (in.) � 1 foot (ft)
6 ft 5 in. � ? in. Think: A foot is a larger unit than an inch.
Multiply to convert 6 ft to inches: 6 ft � 12�inft.
�� 72 in.
Add to find the total: 6 ft 5 in. � 72 in. � 5 in. � 77 in.
Weight16 ounces (oz) � 1 pound (lb)
48 oz � ? lb Think: An ounce is a smaller unit than a pound.There are many ounces in a pound, thus fewer pounds than ounces in the same weight.
Discovering Math, Measurement, Sizes of Standard Units...or, It’s the One
Name Date
Use equivalent measures to convert standard units.Multiply by smaller units per larger unit to convert from a larger unit to a smaller unit. The measurrement becomes a greater number of smaller units.Divide by smaller units per larger unit to convert from a smaller unit to a larger unit. The measurement becomes a lesser number of larger units.
Write each missing number.
Length12 inches (in.) � 1 foot (ft)
3 ft � 1 yard (yd)
40 in. � ? ft 40 in. � 12
�inft.
�� 3 R4 ft
40 in. � 3 ft 4 in.
Weight16 ounces (oz) � 1 pound (lb)
3 �12� lb � ? oz
3 �12� lb � 16
�olbz�
� �72� lb � 16
�olbz�
= 56 oz
3 �12� lb � 56 oz
1. 2 �12� ft � in. [30]
4. 3 �14� ft � in. [39]
2. 1 �34� lb � oz
5. 2 �34� qt � c [11]
3. 2 gal � c [32]
6. 72 in. � yd [2]
Liquid Volume1 pint (pt) � 2 cups (c) Sometimes, more than one 1 quart (qt) � 4 cups (c) conversion is needed.1 quart (qt) � 2 pints (pt) 3 gal � ? cups1 gallon (gal) � 4 qt 3 gal � 3 gal � 4
�gqatl
�� 12 qt
3 gal � 12 qt � 4�qct
�� 48 c
[28]
LEVEL
3
7. 35 in. � ft in. [2] [11]
9. 60 oz � lb oz [3] [12]
11. 20 ft � yd ft [6] [2]
13. 62 in. � ft in. [5] [2]
8. 14 qt � gal qt [3] [2]
10. 57 in. � ft in. [4] [9]
12. 85 oz � lb oz [5] [5]
14. 15 c � qt c[3] [3]
Figures with the same perimeter can have different areas.
Find the perimeter and area of each figure. Which figure in each group has the greatest area?
Discovering Math, Measurement, Areas and Perimeters...or, In and Around
Name Date
LEVEL
2
AREAS AND PERIMETERS
Figures with the same perimeter can have different areas.
Perimeter of Rectangle A Perimeter of Rectangle B Perimeter of Square CP = 12 + 4 + 12 + 4 = 32 P = 10 + 6 + 10 + 6 = 32 P = 8 + 8 + 8 + 8 = 32Perimeter = 32 cm Perimeter = 32 cm Perimeter = 32 cm
Area of Rectangle A Area of Rectangle B Area of Square CA = l � w = 12 � 4 = 48 A = l � w = 10 � 6 = 60 A = l � w = 8 � 8 = 64Area = 48 sq cm Area = 60 sq cm Area = 64 sq cm
As the sides of the rectangles get closer in length, the area increases but the perimeter does not change.
The perimeters are all the same for the rectangles within a group.Predict the figure in each group that will have the greatest area. Then find the perimeter and area of each figure.
Discovering Math, Measurement, Areas and Perimeters...or, In and Around
Name Date
When the lengths of sides of a figure are doubled, keeping the figure the same shape, theperimeter is doubled, but the area is increased by 4 times.
Perimeter of Rectangle A Perimeter of Rectangle BP = 6 + 4 + 6 + 4 = 20 P = 12 + 8 + 12 + 8 = 40Perimeter = 20 cm Perimeter = 40 cm
As the lengths of the sides are doubled, the perimeter doubles.
Area of Rectangle A Area of Rectangle BA = l � w = 6 � 4 = 24 A = l � w = 12 � 8 = 96Area = 24 sq cm Area = 96 sq cm
As the lengths of the sides are doubled, the area is multiplied by 4.
Find the perimeter and area of each figure. Then double the length and width of each figure.Predict the new perimeter and area. Then check the new perimeter and area.
Discovering Math, Measurement, Variability in Measurement...or, Close Encounters
Name Date
LEVEL
2
VARIABILITY IN MEASUREMENT
Using a customary ruler marked in inches and eighths of inches, you can measure reliablyto the nearest �
18�-inch. The smaller the unit of measurement, the more precise the measurement
can be. If the ruler is accurate, smaller divisions allow reliable measurement closer to thetrue value, which are therefore more accurate measurements.
To make an accurate measurement, align the left edge of the item being measured with the left edge or “0” mark on the ruler.
To the nearest �12�-inch, the string is 1�
12� inches long.
To the nearest �14�-inch, the string is 1�
34� inches long.
To the nearest �18�-inch, the string is 1�
58� inches long.
The measurement of 1�58� inches is the most precise, to the nearest �
18� –inch, and the most
accurate since it uses the smallest unit, so it’s closest to the true value.
Which measurement is the most accurate? Explain why.
1.
[2�18� in. is more accurate since the left end of the straw is aligned with the left end of the ruler,
so the recorded length is closer to the true value. The other straw is not aligned at the end.]
2. A scale in the produce section of a grocery store measures weight inpounds, with no smaller intervals. When Jill puts a melon on the scale, it shows the weight to the nearest marking as 2 pounds. When the clerkputs the same melon on a scale at the register, the measurement is 2pounds 5 ounces. Both scales read “0” when nothing is on the scales.Assuming both scales are accurate, which measurement is more accurate?
[The scale at the register is more accurate since it shows smaller units, so its
Discovering Math, Measurement, Variability in Measurement...or, Close Encounters
Name Date
LEVEL
3
The precision and accuracy of a measurement may depend upon the units of measurement used. A length measured to the nearest �
18�-inch
is more precise than a length measured to the nearest inch, since �18�-inch is a smaller unit. If the ruler is accurate, the measurement will usually also be more accurate, because it will be closer to the true value, within �
18� inch
rather than only within a greater interval.
The accuracy of a measurement may depend upon the tool used to measure. A scale that is set at “0” when it is empty is usually more accurate than a scale that is not set at “0.”
Which measurement is the most accurate? Explain why.
1. Lonnie measures a string using a ruler. He says the string is 4�136� inches
long. Randy measures the same string using a different ruler. He saysthe string is 4�
14� inches long. Both friends align the end of the string with
the left ends of their rulers and measure to the nearest marking. Whosemeasurement is more accurate?
[Lonnie’s because he uses the smaller unit, so his measurement is therefore closer to the true value,
to the closest �116� inch rather than only to the closest �
14� inch.]
CHALLENGE
Which measurement is more accurate? Explain.
[1�12� in., because the reported length happens to be closer to the true value.]
With which ruler could you generally make measurements precise to within acloser interval?
[The second, because the intervals are smaller, so you could repeat
Discovering Math, Measurement, Estimation Strategy... or, How About It?
LEVEL
1
Name Date
ESTIMATION STRATEGIES
You can estimate to help you make decisions about money.
Kendra has $8.00 to spend at the book store. She wants to buy a book that costs $4.95 and a magazine that costs $3.19. Does she have enough money to buy both items?
Round each amount to estimate the total.
The book costs about $5.00.The magazine costs about $3.20.$5.00 � $3.20 � $8.20
Compare the total with the amount she has.
$8.20 � $8.00
$8.20 is more than the amount Kendra has. She does not have enough money to buy both items.
Use an estimate to solve each problem.
1. Enrico has $10.00. He wants to buy some watercolors that cost $7.49and a paint brush that costs $1.99. Does he have enough money to buyboth items? Explain.
[Yes: $7.50 � $2.00 � $9.50 and $9.50 � $10.00]
2. Lourdes has $3.00. She wants to buy 4 different markers that cost$0.69 each. Does she have enough money to buy all the markers?Explain.
[Yes. Each marker costs about $0.70 and $0.70 � 4 � $2.80 and $2.80 � $3.00.]
3. Ryan has $15.00. He wants to buy 2 magazines that cost $4.25 eachand a guidebook that costs $8.79. Does he have enough money to buyall the items? Explain.
Discovering Math, Measurement, Estimation Strategy... or, How About It?
Name Date
LEVEL
2
ESTIMATION STRATEGIES
You can estimate to help you make decisions about money.
Corey is able to save $3.00 each week. He wants to save the money to buy a new game. The game costs $29.95. How many weeks will Corey have to save money before he has enough to buy the game?
Savings each week: $3.00 Cost of game: about $30.00
Divide to find about how many weeks Corey will have to save.
Corey will have to save money for about 10 weeks to buy the game.
Use an estimate to solve each problem.
1. Lara can save $4.00 each month. She wants to save the money to buya new pair of skates that cost $38.50. How many months will Lara haveto save money before she has enough to buy the skates?
[about 10 months]
2. Jason plans to save $3.25 each week to buy a birthday gift for hismother. He wants to buy her a vase that costs $45.00. How manyweeks should Jason plan on saving money to have enough to buy thevase?
[about 15 weeks]
3. Eva is saving $2.25 each week to buy a new book that will cost$13.95. How many weeks will Eva have to save money so that she willhave enough to buy the book?
[about 7 weeks]
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[Estimates may vary. Accept reasonable estimates. Sample estimates are given.]
Discovering Math, Measurement, Estimation Strategy... or, How About It?
Name Date
LEVEL
3
[Estimates may vary. Accept reasonable estimates. Sample estimates are given.]
You can estimate to help you make decisions about money.
Paula and Greg want to earn $2,000 to redecorate a room. Paula works Saturdays at a banquet hall. She earns $75 each time she works. Greg works afternoons at a market. He earns $32 each afternoon he works. Paula will work every Saturday until she earns $800. Greg will work 3 afternoons a week until he earns $1200. How many weeks will each person have to work to meet their goals?
Estimate the number of weeks Paula needs to work.$800 � $80 � 10 Since $75 � $80, adjust the estimate: add 1 more week.
Paula needs to work about 11 weeks.
Estimate the number of weeks Greg needs to work.He earns about $30 � 3, or about $90, each week. $1,200 � $90 ≈ $1,200 � $100 � 12 Since $90 � $100, adjust the estimate: add 1 more week.
Greg needs to work about 13 weeks.
Use an estimate to solve each problem.
1. Marc wants to earn $350 to buy a new printer. He does yard workevery weekend and earns $7.50 each hour he works. He works about 8hours every weekend. How many weekends will Marc have to work tomeet his goal?
[about 6 weekends]
2. Rebecca wants to earn $700 to buy a new computer. She works in acrafts shop twice a week. She works 4 hours each time she works andearns $8.10 each hour she works. How many weeks will Rebecca haveto work to meet her goal?
[about 11 weeks]
Inches, feet, yards, and miles are customary units of length.Centimeters, meters, and kilometers are metric units of length.
Different units are used to measure different lengths.
Choose the unit you would use to measure each length. Write inches, feet, or miles.
Choose the unit you would use to measure each length. Write centimeters, meters, or kilometers.
Discovering Math, Measurement, Selecting Units...or, Sizing It Up
Name Date
LEVEL
2
SELECTING UNITS
Different units of measurement are used to measure different lengths:length of a ladybug: use millimeters.height of a cereal box: use inches or centimeters.length of a football field: use feet, yards, or meters.distance between cities: use miles or kilometers.
Choose the customary unit you would use to measure each length.
Choose the metric unit you would use to measure each length.
Customary Units of Lengthinches, feet, yards, miles
Metric Units of Lengthmillimeters, centimeters, meters, kilometers
Discovering Math, Measurement, Selecting Units...or, Sizing It Up
Name Date
LEVEL
3
Use smaller units to measure lesser lengths and larger units to measure greater lengths. Inches are smaller units than feet. Use inches to measure the width of a car window, but use feet to measure the length of a car.
Use smaller units to measure lesser volumes or capacities and larger units to measure greater volumes or capacities.Gallons are larger units than quarts. Use gallons to measure the amount of gas needed tofuel a car, but use quarts to measure the oil a car uses.
Choose the customary unit you would use to measure each.