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Grade 3 Math · World 2: Add-and-Subtract Express · Level 18
Adding and Subtracting to 10,000
Use place value for four-digit sums and differences.
Warm-up, learn, try it together, practice, then a quick check. About 15 minutes.
What children learn in Level 18
- Bigger numbers work the same way. For 3,457 plus 2,318, add each place.
- 7 plus 8 is 15: write 5 and trade 10 ones for a ten. Then 5 tens plus 1 ten plus 1 new ten is 7 tens. 4 hundreds plus 3 hundreds is 7 hundreds. 3 thousands plus 2 thousands is 5 thousands.
- Round numbers can be added in hundreds: 2,400 plus 1,300 is 24 hundreds plus 13 hundreds, which is 37 hundreds, or 3,700.
Georgia's K-12 Mathematics Standards:
- 3.PAR.2.2 — Apply part-whole strategies, properties of operations and place value understanding, to solve problems involving addition and subtraction within 10,000. Represent these problems using equations with a letter standing for the unknown quantity. Justify solutions.