Which of the following numbers will replace the question mark (?) in the given series? 18, 54, 29, 87, 62, 186, ?
- A.174
- B.154
- C.161
- D.156
Explanation
Pattern alternates ×3 and −25: 18×3=54, 54−25=29, 29×3=87, 87−25=62, 62×3=186, 186−25=161. Option 3.