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#1




Biostatistics #13  Probability and cholesterol
Serum cholesterol levels are obtained for four healthy men. The probability that all will fall below the 10th percentile of the distribution of cholesterol for healthy males is:
a. 0.4 b. 1  (0.1)^4 c. (0.1)^4 d. (0.9)^4 e. cannot be determined from these data x^y = x to the power of y * I did a pretty similar question in "UW"... 
#3




my answer e)



#4




Correct Answer is B
Quote:
Answer B. 
The above post was thanked by:  
bebix (06062011) 
#6




I think it's C
Each of them has 10% probability to fall below 10th percentile, so the probability that all of them are below that limit is (0.10)*(0.10)*(0.10)*(0.10), thus (0.10)^4. 
#7




Quote:
probability of four persons falling below 10th percentile =(0.1)^4 
#8




correct answer
Here we could have 2 answers...
Since they did not mention that the distribution of cholesterol for healthy males follows a normal distribution, one could say that the answer is E). (answer from the book) Now, if we assume that the underlying distribution of cholesterol is normal (i did), the answer will be C) Alternative B) is the probability that ALL will fall above 10th p. Thanks! 
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BiostatisticsEpidemiology, Step1Questions 
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