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Nicely made practice sheets about addition.
This is the full version, it contains more than 100 practice sheets.
Section 1: Sum Less Than 5
Section 2: Sum Less Than 10
Section 3: Adding Single-Digit Numbers And Tens
Section 4: Adding Two Single-Digit Numbers
Section 5: Adding Single-Digit and Double-Digit Numbers
Section 6: Sum Less Than 100
Answers are provided.