Transcript 1 - Rooms 12 and 13

Are You Ready for Chapter 5?
Lesson 1: Add Tens
Lesson 2: Count On Tens and Ones
Lesson 3: Problem-Solving Strategy:
Work Backward
Lesson 4: Regroup Ones as Tens
Lesson 5: Add One-Digit Numbers and
Two-Digit Numbers
Lesson 6: Add Two-Digit Numbers
Lesson 7: Estimate Sums
Lesson 8: Add Three Two-Digit Numbers
Lesson 9: Problem-Solving Investigation:
Choose a Strategy
Chapter 5 Review
Select a hyperlink to go to the corresponding slides.
I will use addition facts to
add tens.
4+5
What is the sum?
9
Model the following using cubes:
40 + 50
40 + 50
What is the sum?
90
What is the sum of 4 ones and
5 ones?
9
What is the sum of 4 tens and
5 tens?
90
Add.
60
+ 30
90
20
+ 50
70
Add.
10
+ 40
50
30
+ 30
60
Add.
70
+ 20
90
50
+ 10
60
I will count on by tens and
ones to find sums.
Sara has
26 stickers.
She gets 3 more.
How can Sara
count on to find
how many in all?
Count on 3
from 26.
26
27 28 29
How many
stickers are
there in all?
26
29
27 28 29
What number
sentence tells
about Sara’s
stickers?
26 + 3 = 29
26
27 28 29
Tom also has
26 stickers.
He gets 30 more.
How can Tom
count on to find
how many in all?
Count on by
tens from 26.
26
36
46
56
How many
stickers are
there in all?
56
26
36
46
56
What number
sentence tells
about Tom’s
stickers?
26 + 30 = 56
26
36
46
56
Sara’s Stickers
Tom’s Stickers
Do Sara and Tom still
have the same
number of stickers?
no
Sara’s Stickers
Why not?
Tom added more.
Tom’s Stickers
Count on to add. Write the sum.
34
+ 5
39
57
+ 20
77
Count on to add. Write the sum.
63
+ 30
93
42
+ 7
49
Count on to add. Write the sum.
17
+ 2
19
25
+ 60
85
I will work backward to
solve problems.
What do I need to know?
Underline what you know.
What do I need to find?
Circle the question.
How will you solve this problem?
Work backward.
Work backward to solve this
problem.
What do we already know?
Patty has 2 cards. Hana has
3 cards. Eduardo has 44 cards.
Start with the number of cards
Eduardo has now. Add the cards
he gave away.
44 cards he has now
+ 3 Hana’s cards
47 Eduardo’s and Hana’s cards
47 Eduardo’s and Hana’s cards
+ 2 Patty’s cards
number of cards Eduardo
49 had in the beginning
Eduardo started with 49 cards.
Look back. Does my answer make
sense?
yes; 2 + 3 = 5; 44 + 5 = 49
Work backward to solve.
Clint has 7 more problems to do in
math. He already did 30.
How many problems did he have at
the start?
37 problems
I will regroup to find sums.
regroup
7+6
How can you find out
how many cubes there
are in all?
add
7+6
If there are ten or
more ones on the
workmat, you can
regroup them as one
ten.
7+6
Are there enough to
regroup?
yes
7+6
How many ones are
still in the ones
section?
3
7+6
How many tens are in
the tens section?
1
7+6
What number is one
ten and three ones?
13
Add the ones. Add the tens.
25 + 8
___
2 tens ___
13 ones
Did you regroup?
yes
What is the sum?
33
Add the ones. Add the tens.
12 + 5
___
1 tens ___
7 ones
Did you regroup?
no
What is the sum?
17
I will add one-digit and
two-digit numbers.
How many cubes?
16
How many more?
5
How many ones
altogether?
11
Is 11 more than 10?
yes
Now how many
ten-rods altogether?
2
How many cubes?
1
What is the number?
21
How do you know?
There are two groups of 10 that equal 20
plus one group of 1. That’s 21.
Add.
1
3 4
7
4 1
1
2 8
7
3 5
I will add two-digit
numbers.
24
+ 17
Which digits belong in
the tens place?
2
1
24
+ 17
Which digits belong in
the ones place?
2 4
1 7
1
2 4
1 7
1
Add the ones.
1
2 4
1 7
4 1
Add the tens.
Use the workmat to add.
1
2 6
4 5
7 1
Use the workmat to add.
1
4 7
3 8
8 5
Use the workmat to add.
2 4
5 3
7 7
I will estimate the sum.
round
José has two containers of
marbles. He has 13 marbles in one
container and 29 in the other. He
thinks he has about 40 marbles.
How can we use estimation to
decide if José is right?
Round both numbers. Then add
them to find an estimated sum.
To which ten is 13 rounded?
10
To which ten is 29 rounded?
30
What is the estimated sum?
10 + 30 = 40
Was José’s estimate reasonable?
yes
Round each addend to the
nearest ten. Estimate the sum.
44
+ 53
40
+ 50
__
90
Round each addend to the
nearest ten. Estimate the sum.
48
+ 42
50
+ 40
__
90
I will add three two-digit
numbers.
38
12
+ 25
3
1
2
Model the addends on the
workmat.
8
2
5
38
12
+ 25
Add two addends.
3
1
2
8
2
5
10
38
12
+ 25
1
3
1
2
8
2
5
10
5
Add this sum to the third addend.
38
12
+ 25
75
Add the tens.
1
3
1
2
8
2
5
7
5
Find the sum.
24
16
+ 40
80
13
25
+ 33
71
Find the sum.
28
12
+ 52
92
21
24
+ 12
57
I will choose a strategy to
solve a problem.
What do you know?
Underline what you know?
What do you need to find?
Circle the question.
How will you solve this problem?
One way to solve this problem is to
guess and check.
What do we already know?
Two numbers have a sum
of 16 and a difference of 4.
How can we make a guess about
the answer?
Try different numbers and check the sum
and difference.
8
The sum
+ 8 is right.
16
8
– 8 The difference
is not 4.
0
This answer is not correct.
9
The sum
+ 7 is right.
16
9
– 7 The difference
is not 4.
2
This answer is not correct.
10
+ 6
16
The sum
is right.
10
– 6 The difference
is 4.
4
This answer is correct.
10 and 6 are the numbers.
Look back. Does my answer make
sense?
yes
Choose a strategy. Solve.
Together Tony and
Kerina have 9 pets.
Tony has 3 more
pets than Kerina.
How many pets
does Tony have?
How many pets
does Kerina have?
Tony has 6 pets
and Kerina has
3 pets.
Complete the sentences.
To ____________
is to change
round
the value of a number into one
that is easier to work with.
To ____________
is to take
regroup
apart a number and build it in
another way.
regroup
round
Count on to add. Write the sum.
12
+ 6
18
45
+ 50
95
Round each addend to the
nearest ten. Estimate the sum.
14
+ 18
10
+ 20
__
30
Find the sum.
17
33
+ 24
74
12
12
+ 18
42