Patterns and Number Sequences — Answer Key
Part A: Fill in the Blank
Write the missing word or number on each line.
1. The pattern 2, 5, 8, 11 follows the rule add 3. The next number is 14.
Each number increases by 3, so the rule is add 3.
2. What comes next in 7, 14, 21, 28, 35?
The rule is add 7. 28 + 7 = 35.
3. The pattern 80, 72, 64, 56 follows the rule subtract 8. The next number is 48.
Each number decreases by 8, so the rule is subtract 8.
4. An input-output table uses the rule multiply by 2. If the input is 6, the output is 12.
6 × 2 = 12. Apply the rule multiply by 2 to the input 6.
5. In the pattern 3, 6, 12, 24, each number is multiplied by 2.
Each term is multiplied by 2 to get the next term: 2 × 2 = 4, 4 × 2 = 8, 8 × 2 = 16.
6. If the rule is add 7 and the input is 15, the output is 22.
15 + 7 = 22. Apply the rule add 7 to the input 15.
7. In the pattern 10, 20, 30, 40, the missing number is 20. The rule is add 10.
The rule is add 10. 10 + 10 = 20, so the missing number is 20. The rule number is 10.
8. What comes next in 60, 55, 50, 45, 40?
The rule is subtract 5. 45 − 5 = 40.
9. In the repeating pattern 1, 2, 3, 1, 2, 3, 1, the next number is 2.
The pattern 1, 2, 3 repeats. After 1, the next number is 2.
Part B: Matching
Match each item on the left to the correct answer on the right.
1. Match each item to its correct answer.
Rule: add 4, input = 8
→ 12
15
Rule: subtract 3, input = 20
→ 17
20
Rule: multiply by 3, input = 5
→ 15
12
Rule: add 9, input = 11
→ 20
17
8 + 4 = 12, 20 − 3 = 17, 5 × 3 = 15, and 11 + 9 = 20.