EIAT Number Series and Pattern Recognition 4 — Questions and Answers
Question 1: What is the next number in the series: 3, 9, 27, 81, ___?
- 162
- 243 (Correct answer)
- 189
- 216
Correct answer: 243
Each term is multiplied by 3, so 81 × 3 = 243.
Question 2: Find the missing number: 100, 91, 83, 76, 70, ___?
- 63
- 65 (Correct answer)
- 64
- 66
Correct answer: 65
The differences are −9, −8, −7, −6, −5, so 70 − 5 = 65.
Question 3: What comes next in the pattern: 2, 6, 12, 20, 30, ___?
- 38
- 40
- 42 (Correct answer)
- 44
Correct answer: 42
The differences are 4, 6, 8, 10, 12, so 30 + 12 = 42.
Question 4: An elevator makes trips between floors at intervals of 4, 8, 16, 32 seconds. What is the next interval?
- 48
- 56
- 64 (Correct answer)
- 60
Correct answer: 64
Each interval doubles, so 32 × 2 = 64 seconds.
Question 5: What is the missing value: 5, 10, 20, ___, 80, 160?
- 30
- 35
- 40 (Correct answer)
- 45
Correct answer: 40
Each term doubles, so 20 × 2 = 40.
Question 6: Which number continues the series: 1, 4, 9, 16, 25, ___?
- 30
- 34
- 36 (Correct answer)
- 49
Correct answer: 36
These are perfect squares (1², 2², 3², …), and 6² = 36.
Question 7: A cable tension reading follows: 500, 490, 470, 440, 400, ___. What is next?
- 350 (Correct answer)
- 355
- 360
- 370
Correct answer: 350
The differences decrease by 10 each time (−10, −20, −30, −40, −50), so 400 − 50 = 350.
EIAT Number Series and Pattern Recognition 4
What is the next number in the series: 3, 9, 27, 81, ___?