Difficulty: Easy
Correct Answer: 25
Explanation:
Given data
Concept/Approach
Alternating pattern: −1, +2, −1, +2, −1, +2, ...
Step-by-Step calculation
22 − 1 = 2121 + 2 = 2323 − 1 = 2222 + 2 = 2424 − 1 = 23Next: 23 + 2 = 25
Verification/Alternative
Check two-step cycle repeats consistently.
Common pitfalls
Final Answer
25
Discussion & Comments