Addition Within 10 — Answer Key
Part A: Fill in the Blank
Write the missing word or number on each line.
1. 7 + 2 = 9
7 + 3 = 10. 7 and 3 are make-ten partners, so 3 finishes the ten.
2. 5 + 3 = 8
4 + 5 = 9. Count on from 5 four times to land on 9, or think 5 + 4 which is one less than 5 + 5.
3. 2 + 8 = 10
2 + 8 = 10. Flip it to 8 + 2 and take two hops from 8: 9, 10.
4. 1 + 6 = 7
6 + 1 = 7. Only one more than 6 gets us to 7.
5. 5 + 3 = 8
2 + 1 = 3. If 1 is already there, 2 more brings you to 3.
6. 9 + 0 = 9
4 + 2 = 6. Hold 4 and count two more: 5, 6.
7. 1 + 3 = 4
3 + 2 = 5. Starting at 3, two steps forward reach 5.
8. 5 + 5 = 10
2 + 6 = 8. The gap between 6 and 8 is only 2, so 2 fits in the blank.
9. 3 + 4 = 7
1 + 1 = 2. This is the smallest doubles fact — two ones make a pair, like a pair of shoes.
Part B: Matching
Match each item on the left to the correct answer on the right.
1. Match each item to its correct answer.
5 + 1
→ 6
5
3 + 2
→ 5
6
7 + 3
→ 10
8
4 + 4
→ 8
10
Work out each sum and draw a line to its answer: 4 + 1 is 5; 6 + 3 equals 9; 2 + 6 makes 8; and 0 + 4 stays at 4 because adding zero keeps the number the same.