3's Addition (Mixed)

Gap-fill exercise

Fill in all the gaps, then press "Check" to check your answers. Use the "Hint" button to get a free letter if an answer is giving you trouble. You can also click on the "[?]" button to get a clue. Note that you will lose points if you ask for hints or clues!
1. 8+3=
2. 6+3=
3. 0+3=
4. 4+3=
5. 3+1=
6. 2+3=
7. 3+3=
8. 5+3=
9. 3+7=
10. 9+3=