Percentile - Need some insight here

[karthikpandian19]

Anne scored higher than exactly 14 of the 50 students in her class. She is in the nth percentile. What is n?

14
28
36
72
25

Eventhough it may be a simple percentile problem for many, i am posting this for getting insight into the percentile problems in GMAT. I had a difficulty in understanding the answer??
Experts can you throw light on this topic?

[Anurag@Gurome]

Anne scored higher than exactly 14 of the 50 students in her class. She is in the nth percentile. What is n?

In a population or a sample, the P-th percentile is a value such that at least P percent of the values take on this value or less.

In this case, Anne's score is more than exactly 14 of the 50 students in her class. Hence, (14 + 1) = 15 students scored less than or equal to Anne's score.

Hence, Anne is in 100*(15/50) = 30-th percentile.

If I'm not mistaken, this problem has taken the definition of percentile as the fraction of values that are less than (not equal to) the sample.

Hence, Anne is in 100*(14/50) = 28-th percentile.

[karthikpandian19]

Anurag,

So as a thumb rule can i consider for all percentile problems that "In a population or a sample, the P-th percentile is a value such that at least P percent of the values take on this value or less."?

Anne scored higher than exactly 14 of the 50 students in her class. She is in the nth percentile. What is n?

In a population or a sample, the P-th percentile is a value such that at least P percent of the values take on this value or less.

In this case, Anne's score is more than exactly 14 of the 50 students in her class. Hence, (14 + 1) = 15 students scored less than or equal to Anne's score.

Hence, Anne is in 100*(15/50) = 30-th percentile.

If I'm not mistaken, this problem has taken the definition of percentile as the fraction of values that are less than (not equal to) the sample.

Hence, Anne is in 100*(14/50) = 28-th percentile.

[Anurag@Gurome]

So as a thumb rule can i consider for all percentile problems that "In a population or a sample, the P-th percentile is a value such that at least P percent of the values take on this value or less."?

Yes.

For example, in a test your percentile will indicate how many people has scored less than or equal to you as a fraction of the total number of people who has taken the test.