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Are You Ready for Chapter 14?
Lesson 1: Add Hundreds
Lesson 2: Regroup Ones
Lesson 3: Regroup Tens
Lesson 4: Problem-Solving Strategy: Make a Table
Lesson 5: Estimate Sums
Lesson 6: Subtract Hundreds
Lesson 7: Regroup Tens
Lesson 8: Regroup Hundreds
Lesson 9: Estimate Differences
Lesson 10: Problem-Solving Investigation: Choose a Strategy
Chapter 14 Review
I will add numbers in the hundreds.
How can you solve 500 + 400?
54
00
00
What addition fact can you use to solve this problem?
54
00
00
5 + 4 = 9
What is500 + 400?
54
00
00
0 0
900
9
300 + 200 = ___
500 + 100 = ___
700 + 200 = ___
500
600
900
Add.
400 + 400 = ___800
I will regroup the ones to add three-digit numbers.
How do you solve 611 + 319?
63
11
19
Add the ones. What is 1 + 9?
63
11
19
10
Regroup. 10 ones is the same as 1 ten. Where do we write the 1?
63
11
19
above the numbers in the tens column
1
What do we write in the ones place?
63
11
19
0
1
0
Add the tens. What is 1 + 1 + 1?
63
11
19
3
1
03
Add the hundreds. What is 6 + 3?
63
11
19
9
1
039
What is 611 + 319?
63
11
19
930
1
039
Add.
861
732+ 129
518+ 239
268+ 316
757 584
I will regroup tens to add three-digit numbers.
How do you solve 399 + 148?
31
94
98
31
94
98
Add the ones. What is 9 + 8?
17
31
94
98
How do we regroup 17?
1 ten and 7 ones
1
7
31
94
98
Add the tens. What is1 + 9 + 4?
14
1
7
31
94
98
How do we regroup 14 tens?
1 hundred and 4 tens
1
7
1
4
31
94
98
Add the hundreds. What is 1 + 3 + 1?
5
1
7
1
45
31
94
98
What is399 + 148?
547
1
7
1
45
Add.
408
182+ 226
482+ 255
284+ 243
737 527
I will make a table to solve problems.
What do I know?
Underline what you know.
What do I need to find?
Circle the question.
How will I solve the problem?
I will make a table to find the time that Sonja will leave.
Make a table.
Flight Time
1 2:30
2 4:30
3 6:30
Sonja’s plane will leave at 6:30.
Look back.Is my answer reasonable?
Flight 2 leaves at 4:30.Flight 3 leaves at 6:30.
Flight 1 leaves at 2:30.
yes
Make a table to solve.
Conner read 1 book every week for 6 weeks. Each book had 100 pages. How many pages did he read in all?
600 pages
Week Pages
1 100
2 200
3 300
4 400
5 500
6 600
I will estimate the sums of three-digit numbers.
What is 678 rounded to the nearest ten?
680
678 + 118
What is 118 rounded to the nearest ten?
120
678 + 118
What is the estimated sum of 678 + 118 to the nearest ten?
680 + 120 = 800
678 + 118
What is 678 rounded to the nearest hundred?
700
678 + 118
What is 118 rounded to the nearest hundred?
100
678 + 118
What is the estimated sum of678 + 118 to the nearest hundred?
700 + 100 = 800
678 + 118
What is 404 rounded to the nearest ten?
400
404 + 161
What is 161 rounded to the nearest ten?
160
404 + 161
What is the estimated sum of404 + 161 to the nearest ten?
400 + 160 = 560
404 + 161
What is 404 rounded to the nearest hundred?
400
404 + 161
What is 161 rounded to the nearest hundred?
200
404 + 161
What is the estimated sum of404 + 161 to the nearest hundred?
400 + 200 = 600
404 + 161
Which estimate is closer to the exact answer?
rounding to the tens
404 + 161
I will subtract numbers in the hundreds.
—
63
00
00
Subtract the ones. What is 0 – 0?
00
—
63
00
00
Subtract the tens. What is 0 – 0?
00
0
—
63
00
00
Subtract the hundreds. What is 6 – 3?
03
03
—
63
00
00
When subtracting hundreds, you can ignore the zeros. All that is left is a one-digit number fact which has two zeros after it.
003
—
63
00
00
6 hundreds– 3 hundreds
3 hundreds
003
600– 300
300
Subtract.
600
700– 100
500– 200
400– 300
300 100
I will regroup tens to subtract three-digit numbers.
—
21
87
69
How do you solve 286 – 179?
—
21
87
69
Try to subtract the ones. Can you subtract 9 from 6?
no
—
21
87
69
Regroup the tens. Change one of the tens into ten ones. How many tens does that leave you?
8 – 1 = 7
7
—
21
87
69
How many ones does that give you?
6 + 10 = 16
7 16
—
21
87
69
Now subtract the ones. What is 16 – 9?
7
7 16
7
—
21
87
69
Subtract the tens. What is 7 – 7?
0
7 16
70
—
21
87
69
Subtract the hundreds. What is 2 – 1?
1
7 16
701
—
21
87
69
What is286 – 179?
107
7 16
701
Subtract.
859
873– 14
998– 389
753– 119
609 634
I will regroup hundreds to subtract three-digit numbers.
—
51
35
42
How do you solve 534 – 152?
—
51
35
42
Subtract the ones. What is 4 – 2?
2
2
—
51
35
42
Try to subtract the tens. Can you subtract 5 from 3?
no
2
—
51
35
42
Regroup the hundreds. Change one of the hundreds into 10 tens. How many hundreds does that leave you?
5 – 1 = 4
2
4
—
51
35
42
How many tens does that give you?
3 + 10 = 13
2
4 13
—
51
35
42
Now subtract the tens. What is 13 – 5?
8
2
4 13
8
—
51
35
42
Subtract the hundreds. What is 4 – 1?
3
2
4 13
83
—
51
35
42
What is534 – 152?
382
2
4 13
83
Subtract.
453
518– 65
277– 194
537– 356
83 181
I will estimate the difference of three-digit numbers.
434 – 196
What is 434 rounded to the nearest hundred?
400
434 – 196
What is 196 rounded to the nearest hundred?
200
434 – 196
What is the difference between 400 and 200?
400 – 200 = 200
434 – 196
434 – 196 is about 200. You have rounded numbers to the hundreds to estimate the solution to the problem.
434 – 196
What is 434 rounded to the nearest ten?
430
434 – 196
What is 196 rounded to the nearest ten?
200
434 – 196
What is the difference between 430 and 200?
430 – 200 = 230
434 – 196
434 – 196 is about 230. You have rounded numbers to the tens to estimate the solution to the problem.
598 – 294
What is 598 rounded to the nearest hundred?
600
598 – 294
What is 294 rounded to the nearest hundred?
300
598 – 294
What is the difference between 600 and 300?
600 – 300 = 300
598 – 294
What is 598 rounded to the nearest ten?
600
598 – 294
What is 294 rounded to the nearest ten?
290
598 – 294
What is the difference between 600 and 290?
600 – 290 = 310
598 – 294
Which estimate is closer to the exact answer?
rounding to the hundreds
I will choose a strategy to solve the problem.
What do I know?
Underline what you know.
What do I needto find?
Circle the question.
How will Isolve the problem?
One way is to work backward.
I have 300 cubes left.
I gave 100 cubes to Rikki.
I gave 200 cubes to Polly.
300 + 100 + 200 = 600
I started with 600 cubes.
300
+ 100
+ 200
600
Is my answerreasonable?
600 – 200 = 400 I gave Polly 200 cubes.
400 – 100 = 300 I gave Rikki 100 cubes.
The answer is correct.
Choose a strategy. Solve.
I am a number less than 150. There is a 7 in my ones place. I am greater than 140. What number am I?
147
To ____________ is to take apart a number and write it a new way.
To ____________ is to change the value of a number into one that is easier to work with.
regroup round
Complete the sentences.
regroup
round
Solve.
781
542+ 239
438– 165
263– 116
273 147
Image Bank
Math Tools
Regroup OnesRegroup TensRegroup Hundreds
