Number Writing 0-20 — Answer Key
Part A: Multiple Choice
Circle the best answer for each question.
1. Find the missing number: 16, 17, 18, ___, 20.
A) 19
B) 15
C) 21
D) 18
The sequence adds one, so after eighteen comes nineteen, then twenty, making nineteen the missing number.
2. Ben had 5 cars. Dad gave 4 more. Then he lost 1. How many?
A) 10
B) 8
C) 9
D) 7
Five plus four equals nine, then nine minus one equals eight cars left for Ben.
3. Find the missing number: 12, ___, 14, 15, 16.
A) 11
B) 14
C) 13
D) 10
The sequence adds one each time, so after twelve comes thirteen, then fourteen, making thirteen missing.
4. Anna had 10 pens. She got 3 more, gave 2 away. Total now?
A) 13
B) 9
C) 12
D) 11
Ten plus three equals thirteen, then thirteen minus two equals eleven pens for Anna.
Part B: Fill in the Blank
Write the correct answer on each line.
1. Find the missing number: 0, 1, 2, 3, 4.
The sequence adds one each time, so after two comes three, then four, making three the missing number.
2. Joe had 8 blocks. He used 3, then got 2. He has 7 blocks.
Eight minus three equals five, then five plus two equals seven blocks for Joe.
3. Find the missing number: 18, 19, 20.
The sequence adds one each time, so after nineteen comes twenty, making twenty the missing number.
4. Pam had 4 apples. She got 3, then ate 1. She has 6 apples.
Four plus three equals seven, then seven minus one equals six apples for Pam.
5. Find the missing number: 5, 6, 7, 8, 9.
The sequence adds one each time, so after seven comes eight, then nine, making eight the missing number.