Customary Units of Length

Transcription

Customary Units of Length
Name
15.2
?
Geometry and
Measurement—4.8.A,
4.8.B
Also 4.8.C
MATHEMATICAL PROCESSES
4.1.F, 4.1.G
Customary Units of Length
Essential Question
How can you convert customary units of length?
Unlock
Unlock the
the Problem
Problem
You can use a ruler to measure length. A ruler that is 1 foot long
shows 12 inches in 1 foot. A ruler that is 3 feet long is called a
yardstick. There are 3 feet in 1 yard.
How does the size of a foot compare to the size of an inch?
Activity
Materials ■ 1-inch grid paper ■ scissors ■ tape
STEP 1 Cut out the paper inch tiles. Label each tile 1 inch.
1 inch 1 inch 1 inch 1 inch
1 inch
1 inch
1 inch
1 inch 1 inch 1 inch 1 inch
1 inch
STEP 2 Place 12 tiles end-to-end to build 1 foot. Tape the tiles together.
1 foot
1 inch 1 inch 1 inch 1 inch 1 inch 1 inch 1 inch 1 inch 1 inch 1 inch 1 inch 1 inch
STEP 3 Compare the size of 1 foot to the size of 1 inch.
1 foot
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1 inch 1 inch 1 inch 1 inch 1 inch 1 inch 1 inch 1 inch 1 inch 1 inch 1 inch 1 inch
1 inch
1 inch
So, 1 foot is _ times as long as 1 inch.
Think: You need 12
inches to make 1 foot.
Math Talk
Mathematical Processes
How many inches would
you need to make a yard?
Explain.
Module 15
525
Example 1 Convert larger units to smaller units.
Emma has 4 feet of thread to make some bracelets. How many
inches of thread does Emma have?
Since 1 foot is 12 times as long as 1 inch, you can write feet as inches
by multiplying the number of feet by 12.
Make a table that relates feet and inches.
Feet
Inches
1
12
Think:
1 foot × 12 = 12 inches
2
2 feet × 12 = __
3
3 feet × _ = __
4
4 feet × _ = __
5
5 feet × _ = __
So, Emma has _ inches of thread.
Example 2 Convert smaller units to larger units.
Jason ran 300 feet during recess. How many yards did Jason run?
Make a table that relates feet and yards.
Yards
120
120 feet ÷ 3 =
150
150 feet ÷ 3 =
210
210 feet ÷ _ = __
240
240 feet ÷ _ = __
300
300 feet ÷ _ = __
So, Jason ran _ yards during recess.
Math Talk
Mathematical Processes
Explain how making
a table helped you solve
the problem.
• What if Emma had 5 feet of thread? Would she have enough thread to
make the bracelets? Explain.
526
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Feet
Name
Share
Share and
and Show
Show
1. Compare the size of a yard to the size of a foot.
Use a model to help.
Customary Units of Length
1 foot (ft) = 12 inches (in.)
1 yard (yd) = 3 feet
1 yard (yd) = 36 inches
1 yard
1 yard is _ times as long as _ foot.
Complete.
2. 2 feet = _ inches
3. 3 yards = _ feet
4. 12 feet = _ yards
5. 7 yards = _ feet
6. 144 inches = _ feet
7. 72 feet = _ yards
Math Talk
Mathematical Processes
Problem
Problem Solving
Solving
8.
Multi-Step Joanna has 3 yards
of fabric. She needs 100 inches of fabric to make
curtains. Does she have enough fabric to make
curtains? Explain. Make a table to help.
If you measured the
length of your classroom
in yards and then in feet,
which unit would have a
greater number of units?
Explain.
Yards
Inches
1
2
3
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9.
Justify Hannah’s room is 14 feet wide.
She says that her room is 160 inches wide. Is Hannah
correct? Explain your answer.
Write Math
Show Your Work
Module 15 • Lesson 2
527
Mathematical Processes
M
Model ¥ Reason ¥ Communicate
M
Daily
Daily Assessment
Assessment Task
Task
Fill in the bubble completely to show your answer.
10. A spool of thread contains 6 yards of thread. How many
feet of thread are on the spool?
Yards
Feet
1
3
A
6 feet
2
B
9 feet
3
C
18 feet
D
2 feet
4
5
6
11. Which statement about 8 yards and 25 feet is true?
A
25 feet = 8 yards
B
25 feet < 8 yards
C
8 yards > 25 feet
D
8 yards < 25 feet
12. Multi-Step Carla has 3 feet of ribbon. She needs 38 inches of
ribbon to wrap a present. How many more inches of ribbon
does Carla need?
A
2 inches
B
35 inches
C
29 inches
D
3 inches
TEXAS Test Prep
13. Jim is putting carpet in his basement. The length of his basement
528
A
4 feet
B
15 feet
C
36 feet
D
432 feet
© Houghton Mifflin Harcourt Publishing Company
is 12 yards. How many feet is the length of his basement?
H o mewo rk
and Practice
15.2
Geometry and Measurement—
4.8.A, 4.8.B Also 4.8.C
MATHEMATICAL PROCESSES 4.1.F, 4.1.G
Name
Customary Units of Length
Complete.
1. 3 feet =_ inches
Customary Units of Length
2. 5 yards = _ inches
1 foot (ft) = 12 inches (in.)
1 yard (yd) = 3 feet
1 yard (yd) = 36 inches
3. 4 yards = _ feet
5. 9 feet = _ yards
4. 72 inches = _ yards
6. 60 inches = _ feet
Problem
Problem Solving
Solving
7. Conor has a roll of fence that is 25 feet long. He needs 8 yards
Yards
of fence to go around a flower bed. Does he have enough fence
to go around the flower bed? Explain. Make a table to help you.
Feet
1
2
3
4
8. If you measured the width of a window in inches and then in
feet, which measurement would have the greater number of
units? Explain your answer.
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9. Ginny’s house is 20 yards long. She says that the house is 720 feet long.
Is Ginny correct? Explain your answer.
Module 15 • Lesson 2 529
TEXAS Test Prep
Lesson
Lesson Check
Check
Fill in the bubble completely to show your answer.
A
15 feet = 3 yards
B
15 yards = 3 feet
C
15 feet = 5 yards
D
15 yards = 5 feet
12. Hailey has a 5-foot long extension cord.
60 inches and 6 feet is true. Which
statement did he write?
A
60 inches = 6 feet
B
60 inches > 6 feet
C
6 feet < 60 inches
D
6 feet > 60 inches
13. Alex’s driveway is 27 yards long and
She wants to know its length in inches.
How many inches long is the cord?
10 yards wide. How many feet long is
the driveway?
A
60 inches
A
9 feet
B
180 inches
B
81 feet
C
15 inches
C
972 feet
D
48 inches
D
324 feet
14. Multi-Step A roll of tape is 50 yards long.
How many pieces of tape 2 inches long can
be cut from the tape?
530
11. The statement Evan wrote comparing
A
150
B
9,000
C
900
D
300
15. Multi-Step Vicky has a 50 inch roll of
ribbon. She uses 3 feet of the ribbon to
wrap a gift. How many inches of ribbon
does she have left?
A
4 inches
B
41 inches
C
14 inches
D
24 inches
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10. Which statement is true?