PI Number Series Problems 4 — Questions and Answers
Question 1: What is the next number: 120, 60, 20, 5, ___?
- 1
- 1.25 (Correct answer)
- 2
- 2.5
Correct answer: 1.25
Divide by 2, then by 3, then by 4 — the next step divides by 4, so 5 ÷ 4 = 1.25.
Question 2: Find the missing number: 3, 6, 11, 18, ___, 38
- 25
- 27 (Correct answer)
- 28
- 29
Correct answer: 27
Differences are 3, 5, 7, 9, 11 — odd numbers, so 18 + 9 = 27, and 27 + 11 = 38 confirms it.
Question 3: What comes next: 64, 32, 16, 8, 4, ___?
- 0
- 1
- 2 (Correct answer)
- 3
Correct answer: 2
Each term is halved, so 4 ÷ 2 = 2.
Question 4: Complete the series: 2, 6, 18, 54, ___
- 108
- 144
- 162 (Correct answer)
- 216
Correct answer: 162
Each term is multiplied by 3, so 54 × 3 = 162.
Question 5: What is the next term: 10, 10, 20, 60, 240, ___?
- 480
- 720
- 1200 (Correct answer)
- 1440
Correct answer: 1200
Multiply by 1, 2, 3, 4, 5 — the next multiplier is 5, so 240 × 5 = 1200.
Question 6: Find the missing number: 15, 13, 16, 12, 17, 11, ___
- 10
- 12
- 17
- 18 (Correct answer)
Correct answer: 18
Two interleaved sequences: 15, 16, 17, 18 (+1) and 13, 12, 11 (−1), so the next is 18.
Question 7: What comes next: 0.5, 1, 2, 4, 8, ___?
- 12
- 14
- 16 (Correct answer)
- 18
Correct answer: 16
Each term doubles, so 8 × 2 = 16.
PI Number Series Problems 4
What is the next number: 120, 60, 20, 5, ___?