Addition Within 10 — Answer Key
Part A: Multiple Choice
Circle the best answer for each question.
1. Sam has 3 red balls and 6 blue balls. How many balls does Sam have in all?
A) 8
B) 9
C) 7
D) 10
The frog caught 6 flies plus 4 more. 6 + 4 = 10 flies in all.
2. There are 4 birds on a branch. Then 4 more land on it. How many birds are there now?
A) 7
B) 6
C) 9
D) 8
4 + 3 = 7, not 8. The other choices all add up to 8, but this one does not.
3. Mia picks 2 daisies and 5 roses. How many flowers does she have altogether?
A) 8
B) 6
C) 7
D) 9
3 + 4 = 7. You can check by counting up 4 from 3 to reach 7.
4. A pond has 1 frog. Then 8 more frogs jump in. How many frogs are in the pond?
A) 10
B) 8
C) 9
D) 7
Lily starts with 2 flowers and picks 5 more. 2 + 5 = 7 flowers in all.
Part B: Fill in the Blank
Write the correct answer on each line.
1. 4 + 5 = 9
Think: what number plus 3 makes 8? Since 5 + 3 = 8, the missing number is 5.
2. 3 + 7 = 10
Think: 6 plus what number makes 9? Count up from 6 to 9 and you count 3 more.
3. 6 + 2 = 8
Adding 0 to 7 still gives 7. Zero plus any number equals that same number.
4. There are 5 cats and 4 dogs. There are 9 pets in all.
Think: 4 plus what number makes 10? Count up from 4 to 10 and you count 6 more.
5. I see 2 stars and 7 moons. I see 9 things in the sky.
Think: what number plus 1 makes 9? Since 8 + 1 = 9, the missing number is 8.