5LB ,CHAP-22, NO-37

[anik1989]

HI tommy, i can not understand the explanation of the book for this question, can you simplify for me?

PLEASE EXPLAIN:
The outcome of a standardized test is an integer between 151 and 200, inclusive. The percentiles of 400 test
scores are calculated, and the scores are divided into corresponding percentile groups.

Quanti ty A

Minimum number of integers between 151 and 200,
inclusive, that include more than one percentile group

Which of the following would the data pattern shown best describe?

Quanti ty B
Minimum number of percentile
groups that correspond to a score of
200

[tommywallach]

Hey Anik,

Be careful. You accidentally put some text from the NEXT question in there, which is confusing.

This question is actually about logic, not statistics.

If 400 people get a score between 151 and 200, you have to have at least one percentile group with multiple people in it (for example, you could have all 400 people getting a 162, in which case there's JUST one group with more than one percentile score in it, or you could get 100 people each on 152, 153, 154, and 155, in which case there are four groups with more than one percentile score). The "minimum" would be 1 though (as in my 162 example). So Quantity A is 1.

Quantity B is zero, because nobody has to get a 200. (As stated, everyone could have a 162.)

The answer is A.

-t