🧮 Part 1: Mental Math and Breaking Apart

Instructions: Solve these addition problems using mental math or by breaking apart numbers. Show your work in the box below each problem.

1. 12 + 5 = _____

2. 15 + 6 = _____

3. 18 + 4 = _____

4. 14 + 7 = _____

🔄 Part 2: Addition with Regrouping

Instructions: These problems need regrouping (carrying). Show your work step by step.

5. 16 + 7 = _____

6. 19 + 9 = _____

7. 13 + 8 = _____

8. 17 + 6 = _____

9. Word Problem: Lila had 19 marbles. She found 7 more marbles under her bed. How many marbles does Lila have now?

Answer: _____ marbles

10. Vocabulary Match: Draw a line to match each word with its definition.

Sum

Regrouping

Fact Families

Equal Sign (=)

Decompose

To break a number into parts

The answer in an addition problem

When you carry over a ten

Related addition and subtraction facts

Shows that two amounts are the same