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#1




probability question!
A serological test for detecting prostate cancer is negative in 95% of the cases. If the test is used with 8 consecutive blood samples taken from patients without the disease, what is the probability of getting at least one positive test result?
A. 10.05*8 B. 0.05*8 C. 0.05 raised to the power 8 D. 0.95 raised to the power 8 E. 10.95 raised to the power 8 Please answer with explanation. 
#2




A serological test for detecting prostate cancer is negative in 95% of the cases. If the test is used with 8 consecutive blood samples taken from patients without the disease, what is the probability of getting at least one positive test result?
A. 10.05*8 B. 0.05*8 C. 0.05 raised to the power 8 D. 0.95 raised to the power 8 E. 10.95 raised to the power 8 Explanation Test is Truly Negative in 95% of the cases, and Falsely Positive in 5%. The scenario states that the test is used with 8 blood samples. Each testing should be assumed to be an independent event. Than mean that each time the test is performed in 1 blood sample there is 0.95 (95%) probabilities that the test will give a True Negative result and 0.05 (5%) probabilities that the test will give a False Positive result. 
The above post was thanked by:  
MzLizMD (03092012) 
#3




why not c?
why is it not c?? ughhhhh i was never good with the exponents stuff

#4




.05*8
Quote:
which is .05 per patient and to get value for all .05*8??????
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#5




anyone??
can any1 explain this please?? I think the answer is C. i dont understand why it is E ... UW says its E .. i just dont get it!

#6




all i know is this > C & E are the same!!
C. 0.05 raised to the power 8 E. 10.95 raised to the power 8 explanation? because 1 0.95 = .05 i sure do know my math :P 
#7




lol no let me rewrite that one. option E. is 1(0.95raised to the power 8!) .. C & E are different! my bad, i didnt write the options clearly!

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BiostatisticsEpidemiology, Step1Questions 
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