Correct Answer - Option 3 : 5
Given:
?, 18, 57, 174, 525, 1578
Concept Used:
Series is continuously in this order = × 3 + 3.
Calculation:
The series follows the following pattern:
⇒ ? × 3 + 3 = 18
⇒ 18 × 3 + 3 = 57
⇒ 57 × 3 + 3 = 174
⇒ 174 × 3 + 3 = 525
⇒ 525 × 3 + 3 = 1578
Value of ? × 3 + 3 = 18
⇒ ? = (18 – 3)/3
⇒ ? = 15/3
⇒ 5
∴ The required value of "?" is 5.