In this activity, we will learn how to add two numbers using two methods.
Example
Add the numbers below:
22,478 + 15,622
Method 1
1. Add the ten thousands 20,000 + 10,000 = 30,000
2. Add the thousands 2,000 + 5,000 = 7,000
3. Add the hundreds 400 + 600 = 1,000
4. Add the tens 70 + 20 = 90
5. Add the ones 8 + 2 = 10
6. Add the total for the answer below, making sure to line up the numbers in their correct place value columns.
+
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2
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2
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4
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7
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8
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1
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5
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6
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2
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2
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|
|
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3
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0
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0
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0
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0
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|
|
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7
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0
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0
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0
|
|
|
|
1
|
0
|
0
|
0
|
|
|
|
|
|
9
|
0
|
|
|
|
|
|
1
|
0
|
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3
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8
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1
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0
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0
|
Method 2
This is column addition with exchanging (or carrying) if a column adds to 10 or more.
1. Add the ones 8 + 2 = 10. Write the 0 in the ones column, and exchange the one ten by carrying the 1 to under the tens column.
2. Add the tens column, including the exchanged 1. Add 7 + 2 + 1 = 10. Write the 0 in the tens column and exchange the 1 by putting it under the hundreds column.
3. Add the hundreds column, including the exchanged 1. Add 4 + 6 + 1 = 11. Write the 1 in the hundreds column and exchange the 1 by putting it under the thousands column.
4. Add the thousands column, including the exchanged 1. Add 5 + 2 + 1 = 8
5. Add the ten thousands column, 2 + 1 = 3
So in summary:
22,478 + 15,622 = 38,100
For the questions in this activity, you can choose which method you prefer, or have a go at using both!