Subtraction Within 20 — Answer Key
Part A: Solve the Subtraction Problems
Subtract the numbers. Write the answer on the line.
7
-3
4
9
-5
4
10
-4
6
8
-2
6
6
-1
5
10
-7
3
9
-6
3
8
-5
3
Part B: Fill in the Missing Number
Complete each sentence by writing the missing number on the line.
1. Start with 9, take away 4, and you have 5 left.
9 - 4 = 5.
2. Start with 10, take away 3, and you have 7 left.
10 - 3 = 7.
3. Start with 8, take away 6, and you have 2 left.
8 - 6 = 2.
4. Start with 7, take away 5, and you have 2 left.
7 - 5 = 2.
5. Start with 10, take away 8, and you have 2 left.
10 - 8 = 2.
Part C: True or False
Read each statement. Write True or False on the line.
1. 10 - 5 = 5
True False
True -- 10 - 5 = 5.
2. 9 - 3 = 5
True False
False -- 9 - 3 = 6, not 5.
3. 8 - 4 = 4
True False
True -- 8 - 4 = 4.