Add within 1000 (topic 10)

When you solve a problem with partial sums, you start in the ______.

• Tens

• Hundreds

• Ones

• Where ever you regroup

When you solve a problem with standard algorithm, you start in the _____.

• Ones

• Tens

• Hundreds

• Where ever you regroup

Show how to add 344 + 236 on the open number line.

a

b

d

e

f

g

h

574

+6

580

544

344

+200

+30

584

+100

Match the following

• Open number line

• 
• Compensation

• 
• Using a model

• 
• Partial sums

• 
• Standard algorithm

• 

What is the sum to the equation solved on this open number line?

Was this problem solved correctly?

• Yes

• No

Now you solve the problem correctly: 347+454=

Fill in the missing information.

c

d

e

b

g

a

f

2 (ones)

2 (tens)

6

9

1

0

4

8

What is 450 + 100?

What is 330+10?