SOLUTION: Seven observations are drawn from a population with unknown continuous distribution. What is the probability that the least and the greatest observations bracket the median?

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Question 1164706: Seven observations are drawn from a population with unknown continuous distribution. What is the probability that the least and the greatest
observations bracket the median?

Found 2 solutions by solver91311, ikleyn:
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


You are going to make seven observations of the data. There is a finite probability that all seven of the observations are greater than the median, and there is an equal probability that all seven observations are less than the median. Since the definition of the median of a set of data is that value such that exactly half of the values are greater and half of the values are less than the median, the probability that any given observation is greater than the median is 0.5, and the probability that any given observation is less than the median is also 0.5.

The situation is precisely the same as flipping a fair coin seven times in a row. And the question asked is what is the probability that you don't get either seven heads in a row or seven tails in a row.



You can do your own arithmetic.

John

My calculator said it, I believe it, that settles it


Answer by ikleyn(52894) About Me  (Show Source):
You can put this solution on YOUR website!
.

In my view, the problem is posed / formulated INCORRECTLY.


Had it be formulated correctly, it would be state that the distribution is uniform on certain interval
(instead of saying "continuous")


and would ask  " What is the probability that the least and the greatest
observations bracket the mid point of the interval"
(instead of using the term "median", which is AMBIGUOUS in this context).



It is Math, where every word/term in the condition does matter, and every inaccurately used term 
breaks the meaning totally or makes it unclear.



How the problem is posed in the given post, it is not a Math.