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regrouping tens
When we have more than 9 tens, we can regroup 10 tens into 1 hundred.
18 tens 1 hundred 8 tens
Example 3. Add 153 + 174.
Solution. Write the numbers in columns and add them.
Step 1. Add the ones.
H T O
3 + 4 = 7 ones
1 5 3
+ 1 7 4
7
Step 2. Add the tens and regroup.
5 + 7 = 12 tens = 1 hundred 2 tens
Write 2 in the tens place and carry over
1 to the hundreds column.
H T O
1
1 5 3
+ 1 7 4
2 7
Step 3. Add the hundreds. H T O
1 + 1 + 1 = 3 hundreds 1
Write 3 in the hundreds place. 1 5 3
Therefore, 153 + 174 = 327.
+ 1 7 4
3 2 7
41
Addition
