Objective:
• Use a written method to add pairs of 3-digit
numbers
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Stepping Up Term 2
Week 2 Day 2
‘Expanded addition,’ e.g. 429 + 367
Step 1: Expand
horizontally.
429 + 367
400 20 9
300 60 7
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Step 2: Add the ones.
Make sure any tens are
written in the tens
column above the line.
400 20 9
300 60 7
10
6
Stepping Up Term 2
Week 2 Day 2
Step 3: Add the tens.
400 20 9
300 60 7
10
90 6
Step 4: Add the
hundreds. Find the
total.
400 20 9
300 60 7
10
700 90 6
429 + 367 = 796
Hint: Check that your answer looks reasonable!
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Stepping Up Term 2
Week 2 Day 2
‘Compact addition’ for 429 + 367
Step 1: Write the
numbers in columns,
one above the other.
100s 10s 1s
4 2 9
3 6 7
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Step 2: Add the ones.
Write the tens in the
10s column.
100s 10s 1s
4 2 9
3 6 7
1
6
Stepping Up Term 2
Week 2 Day 2
Step 3: Add the tens,
including the extra one.
Write the hundreds in
the 100s column.
100s 10s 1s
4 2 9
3 6 7
1 1
9 6
Step 4: Complete the
addition by adding the
hundreds.
100s 10s 1s
4 2 9
3 6 7
1
7 9 6
Hint: Check that your answer looks reasonable!
© Hamilton Trust
Stepping Up Term 2
Week 2 Day 2
Talk each other through the steps in each method…
Expanded
Compact
700 90 6
4 8 6
2 4 1
+ 1
7 2 7
400 20 9
300 60 7
10
Which method
do you prefer?
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Stepping Up Term 2
Week 2 Day 2
Choose to use either expanded or compact
addition to calculate the following:
Can you make it all the way round the circle?
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Stepping Up Term 2
Week 2 Day 2