Lesson 6.1
Reteach
Name
Draw to Represent
3-Digit Addition
Add 213 and 124.
Draw quick pictures of 213 and 124.
Hundreds
Tens
Ones
Count the hundreds, tens, and ones.
3
hundreds
Write the number.
3
7
tens
ones
337
Draw quick pictures. Write how many hundreds,
tens, and ones in all. Write the number.
1. Add 135 and 214.
Hundreds
Tens
Ones
hundreds
tens
ones
2. Add 121 and 143.
Hundreds
Tens
Ones
hundreds
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tens
ones
Reteach
Lesson 6.1
Enrich
Name
Addition Triplets
One addend is in standard form, but
the other is missing! Draw a quick
picture to find the unknown addend.
1.
2.
542
+
647
+
999
3.
888
4.
401
+
250
+
777
666
Writing and Reasoning How did you decide what
to draw for Exercise 3? Explain.
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6-6
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Lesson 6.2
Reteach
Name
Break Apart 3-Digit Addends
743
+ 124
_
Break apart each addend.
Write the value of each digit.
743 =
700 + 40 + 3
124 =
100 + 20 + 4
Add the hundreds, tens, and ones.
Then add these sums together.
Hundreds
743
+124
Tens
Ones
700 + 40 +
100 + 20 +
800 + —
60 +
3
4
7
867
—=—
Break apart the addends to find the sum.
Hundreds
1.
Tens
Ones
253
+
+
+
536
_
+
+
+
+
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=
Reteach
Lesson 6.2
Enrich
Name
Domino Break
Each set of dominoes shows a 3-digit addend
on top and another on the bottom. Break
apart the addends to find the sum.
2.
1.
600 + 40 +
100 + 10 +
755
3.
3
2
+
+
+
+
4.
+
+
+
+
+
+
+
+
5.
6.
+
+
+
+
+
+
+
+
Writing and Reasoning Draw your own set of dominoes
to show 3-digit addition. Give it to a classmate to solve.
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Lesson 6.3
Reteach
Name
3-Digit Addition:
Regroup Ones
Add.
318
+
256
_
Hundreds
Tens
Ones
Hundreds Tens
B
Ones
Hundreds Tens
Ones
3
2
+
Add the ones.
Hundreds
14
8+6=—
Tens
Ones
Do you need to
regroup?
+
yes
—
Regroup 10 ones as 1 ten.
Add the tens.
7
1+1+5 =—
3
2
Hundreds
Tens
Ones
1
5
1
B
1
5
*WPFTGFU 6GPU
Add the hundreds.
+
5
3+2=—
B
5 7
8
6
8
6
4
1PGU
Write the sum.
1.
Hundreds Tens
+
5
1
B
2.
Ones
2
4
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6
2
Hundreds Tens
+
6-9
4
3
B
5
3
Ones
7
5
Reteach
Lesson 6.3
Enrich
Name
3-Digit Scramble
Use each digit once to make two addends for a
problem in which you regroup ones. Solve.
1.
6, 5, 3, 1, 2, 4
Hundreds
2.
Tens
Ones
Hundreds
+
3.
4, 4, 1, 3, 3, 9
Tens
Ones
+
2, 1, 3, 7, 2, 4
Hundreds
4.
Tens
4, 3, 2, 2, 1, 6
Ones
Hundreds
+
Tens
Ones
+
Writing and Reasoning How did you make sure
you would need to regroup ones?
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Enrich
Lesson 6.4
Reteach
Name
3-Digit Addition: Regroup Tens
Add.
271
+
158
_
Hundreds
Tens
Ones
Add the ones.
BB
2
1
+
9
1+8=—
Add the tens.
Hundreds Tens
Hundreds
Tens
Ones
Hundreds Tens
1 B
B
12
7+5=—
Do you need to
Add the hundreds.
2
1
+
yes
regroup?
—
Regroup 12 tens
as 1 hundred 2 tens.
Hundreds
Tens
7
5
Ones
7
5
2
Hundreds Tens
1 B
B
4
1+2+1 =—
+
2
1
4
7
5
2
Ones
1
8
9
Ones
1
8
9
Ones
1
8
9
Write the sum.
1.
Hundreds Tens
BB
+
2
1
Ones
6
4
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2.
4
5
Hundreds Tens
BB
+
6-11
2
6
3
0
Ones
2
6
Reteach
Lesson 6.4
Enrich
Name
Triple Digits
Use the numbers on the shirts to make an addition
problem in which you regroup tens. Write the sum.
1.
2.
1
8
6
3
7
4
4
5
2
1
6
5
3
9
1
4
5
2
+
3.
+
1
7
2
6
5
3
4.
+
+
Writing and Reasoning Write your own 3-digit
addition problem in which you regroup tens. Give it to a
classmate to solve.
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Enrich
Lesson 6.5
Reteach
Name
Addition: Regroup
Ones and Tens
Sometimes, you may need to regroup
more than once.
189
+
623
_
1
Step 1 Add the ones.
There are 12 ones in all.
Regroup 12 ones as 1 ten 2 ones.
1 8 9
+6 2 3
2
1 1
Step 2 Add the tens.
There are 11 tens in all.
Regroup 11 tens as 1 hundred 1 ten.
1 8 9
+6 2 3
1 2
Step 3 Add the hundreds.
There are 8 hundreds in all.
1 1
1 8 9
+6 2 3
8 1 2
Write the sum.
1.
2.
2 7 8
+ 4 6 5
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3.
1 5 7
+ 7 7 1
6-13
3 6 4
+ 4 1 9
Reteach
Lesson 6.5
Enrich
Name
Paint by Regrouping
Find each sum. Color the problem blue if
you regrouped twice. Color the problem
green if you regrouped once. Color the
problem yellow if you did not regroup.
1.
2.
127
+
293
__
4.
3.
785
+
152
__
5.
378
+
204
__
7.
6.
561
+
327
__
8.
237
+
522
__
825
+
123
__
486
+
335
__
9.
287
+
536
__
709
+
216
__
Writing and Reasoning Why do you sometimes
need to regroup in 3-digit addition problems?
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Lesson 6.6
Reteach
Name
Problem Solving • 3-Digit
Subtraction
There were 237 books on the shelves.
Mr. Davies took 126 books off the shelves.
How many books were still on the shelves?
Unlock the Problem
What do I need to find?
how many books
———
were still on the shelves
What information do
I need to use?
237
There were
books on
—
the shelves.
126
Mr. Davies took
books
—
off the shelves.
Show how to solve the problem.
There were
111
—
books still on the shelves.
Make a model to solve. Then draw
a quick picture of your model.
1. Mr. Cho has 256 pencils.
Then he sells 132 pencils.
How many pencils does
he have now?
—
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pencils
Reteach
Lesson 6.6
Enrich
Name
What Is the Difference?
Use the information on the farmer’s list to
write and solve the subtraction problem.
1. How many
more oranges
than apples
are there?
112
— more oranges
2. How many
more bananas
than pears
are there?
more bananas
3. How many
more roses
than lilies
are there?
more roses
4. How many
more daisies
than violets
are there?
more daisies
Writing and Reasoning Use the list to write your
own subtraction problem. Have a classmate solve it.
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Lesson 6.7
Reteach
Name
3-Digit Subtraction:
Regroup Tens
Subtract.
463
317
__
Hundreds
Tens
Ones
Are there
enough ones
to subtract 7?
—
Regroup 1 ten as 10 ones.
no
There are 13 ones
—
5 tens.
and
—
Hundreds
Tens
Ones
Hundreds
4
3
-
6
13 - 7 = —
Hundreds
4
5-1=—
4
3
-
Subtract the ones.
Subtract the tens.
Hundreds
Tens
Ones
Subtract the hundreds.
Hundreds
4
3
-
1
4-3=—
Tens
Ones
6
1
3
7
Tens
Ones
5
13
6
1
3
7
BB
BB
6
Tens
Ones
5
13
6
1
3
7
6
BB
1
4
Solve. Write the difference.
1.
Hundreds
-
8
3
Tens
Ones
6
2
2
8
BB
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2.
Hundreds
-
6-17
6
2
Tens
Ones
7
4
8
5
BB
Reteach
Lesson 6.7
Enrich
Name
Subtraction Steps
Solve each subtraction problem.
7
- 1
9
2
3
9
5
- 2
3
1
8
9
9
- 1
7
1
5
8
6
-2
6
1
4
7
6
- 1
5
1
7
9
5
-1
3
1
8
9
8
-3
5
1
7
9
3
-1
2
0
8
9
B
B
3 1 9
-1
1
9
Writing and Reasoning Write your own
3-digit subtraction problem that has no regrouping.
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Lesson 6.8
Reteach
Name
3-Digit Subtraction:
Regroup Hundreds
Subtract.
326
174
__
Hundreds
Tens
Ones
Are there
enough tens to
subtract 7 tens?
Tens
2
12
3
1
2
7
Hundreds
Tens
2
12
3
1
2
7
Ones
B BB
Subtract the ones.
2
6-4=—
Hundreds
-
no
—
6
4
2
Regroup 1 hundred as 10 tens.
Now there are
and
2
12
—
hundreds.
tens
—
Subtract the tens.
Hundreds
Tens
Ones
5
12 - 7 = —
B BB
-
Subtract the hundreds.
Ones
1
1
2-1=—
5
6
4
2
Solve. Write the difference.
1.
Hundreds
Tens
Ones
6
2
7
6
9
1
B BB
-
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2.
Tens
Ones
5
2
2
9
5
3
B BB
-
6-19
Hundreds
Reteach
Lesson 6.8
Enrich
Name
Check It Out
Solve the subtraction problem. Then complete the
addition problem to check your work.
1.
6 15
9 7/ 5/
2 5 8
__
7 17
3.
5.
6 27
3 46
__
5 4 6
-1 7 3
__
1
717
2.
+
2 5 8
__
8 4 9
3 5 5
__
+
3 5 5
__
7 98
4 68
__
+
4 6 8
__
4 3 8
2 7 0
__
+
2 7 0
__
975
4.
+ 3 4 6
__
6.
+
1 7 3
__
Writing and Reasoning Why can you use
addition to check your subtraction?
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Enrich
Lesson 6.9
Reteach
Name
Subtraction: Regroup
Hundreds and Tens
You may need to regroup more than once.
282
198
_
Regroup 1 ten as 10
ones. Subtract the ones.
Regroup 1 hundred as
Subtract the hundreds.
10 tens. Subtract the tens.
17
7 12
17
1 7 12
2 8 2
-1 9 8
1 7 12
2 8 2
-1 9 8
2 8 2
-1 9 8
4
84
84
Solve. Write the difference.
1.
4.
481
176
__
2.
746
28
__
3.
33 1
14 8
__
39 5
-1 3 1
5.
52 4
26 5
__
6.
74 8
-6 0 3
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Reteach
Lesson 6.9
Enrich
Name
Subtraction Squares
Start at the top right circle. Subtract to
find the missing number in each circle.
1.
843 - 371 =
-
-
189
=
=
718 2.
=
972 - 384 =
-
-
297
=
=
621 -
=
Writing and Reasoning How is regrouping in
subtraction different from regrouping in addition?
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Lesson 6.10
Reteach
Name
Regrouping with Zeros
Subtract 138 from 305.
There are not enough ones
to subtract 8.
Hundreds
Tens
2 10
Ones
3/ 0/ 5
138
__
Since there are 0 tens,
regroup 3 hundreds as
2 hundreds 10 tens.
Hundreds
Then regroup 10 tens 5 ones
as 9 tens 15 ones.
Tens
Ones
9
2 10 15
3 0 5
/
1 3 8
__
Subtract the ones.
7
15 - 8 = 7
Hundreds
Subtract the tens.
Tens
Ones
9-3=6
3 0 5
-1 3 8
16 7
Subtract the hundreds.
2-1=1
So, 305
9
2 10 15
167 .
- 138 = —
Solve. Write the difference.
1.
8 0 1
3 7 5
__
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2.
6 9 3
2 4 1
__
6-23
3.
9 0 7
6 2 4
__
Reteach
Lesson 6.10
Enrich
Name
Mystery Number
Subtract to find each difference.
Color the box for each difference with a 3 in the
hundreds place to discover the mystery number.
4 0 7
2 5 9
__
9 0 1
5 3 9
__
7 0 2
3 5 5
__
7 0 4
3 5 2
__
8 0 9
3 7 9
__
6 0 9
2 6 9
__
3 0 3
1 1 1
__
5 0 8
1 1 9
__
4 0 2
1 7 4
__
5 0 8
1 8 3
__
8 0 8
4 3 7
__
9 0 2
5 3 8
__
Writing and Reasoning What is the mystery number? —
When do you need to regroup hundreds in a subtraction problem?
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Enrich