To determine your JEE Main 2025 score and percentile, let's break down the calculation process:

Calculating Your Raw Score

1. Correct Answers: You attempted 160 questions, and assuming the remaining 2 questions were wrong, you got 158 questions correct.

2. Raw Score: For each correct answer, you get 4 marks. So, your raw score would be: 158 correct answers * 4 marks = 632 marks.

Normalization and Percentile Calculation

1. Normalization: Since JEE Main is conducted in multiple sessions, the scores are normalized to ensure fairness. This process involves calculating the percentile score based on the relative performance of candidates in each session.

2. Percentile Score: Your percentile score of 77 indicates that you performed better than 77% of the candidates who appeared for the exam.

Possible Reasons for the Discrepancy

1. Normalization Effect: The normalization process might have affected your score, leading to a lower percentile than expected.

2. Difficulty Level: The exam might have been more challenging than you anticipated, resulting in a lower percentile score.

3. Number of Candidates: The number of candidates appearing for the exam might have been higher than expected, affecting the percentile calculation.

Keep in mind that the percentile score is a relative measure, and it's essential to focus on your absolute score and performance.