Addition Within 10 — Answer Key
Part A: Fill in the Blank
Write the missing word or number on each line.
1. 5 + 4 = 9
To reach 9 from 4, you need 5 more, since 5 + 4 = 9. Counting up from 4 — 5, 6, 7, 8, 9 — takes 5 steps.
2. 6 + 2 = 8
Start at 6 and count up to 8: that is two jumps, so 6 + 2 = 8.
3. 3 + 7 = 10
Think about how far 7 is from 10. You need 3 more to make a ten, and 3 + 7 = 10.
4. 3 + 3 = 6
3 doubled makes 6, so 3 + 3 = 6. The missing number matches the 3 already there.
5. 4 + 1 = 5
5 is just one more than 4, so 4 + 1 = 5. Adding 1 means counting up by a single step.
6. 8 + 2 = 10
Eight needs 2 more to become 10, because 8 + 2 = 10. Pairs that make 10 are useful to remember.
7. 5 + 2 = 7
Counting up from 2 by ones — 3, 4, 5, 6, 7 — gets to 7 in 5 jumps, so 5 + 2 = 7.
8. 4 + 6 = 10
4 plus 6 equals 10, since 4 and 6 are partners that make a ten together.
9. 1 + 5 = 6
Only 1 more is needed to turn 5 into 6, because 1 + 5 = 6.
Part B: Matching
Match each item on the left to the correct answer on the right.
1. Match each item to its correct answer.
2 + 5
→ 7
4
6 + 3
→ 9
7
1 + 3
→ 4
10
4 + 6
→ 10
9
Each addition pairs with its sum: 2 + 5 = 7, 6 + 3 = 9, 1 + 3 = 4, and 4 + 6 = 10. Adding the two parts of each expression gives the total on the right.