NBME 12 statistic question

[Kovach]

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Assume that any single laboratory test in a three-test battery obtained from a healthy volunteers has a 5% of falling outside of a normal range. Which of the following is the closest probability that a healthy person will have normal results for all three test?
A- 5%
B- 40%
C- 80%
D- 95%

And please explain why! Are these events independent or mutually exclusive?

 

[CaptainSSO]

are you sure those are the right answer choices?

i'm thinking it should just be (.95)(.95)(.95) = .856

 

[Kovach]

are you sure those are the right answer choices?

i'm thinking it should just be (.95)(.95)(.95) = .856

Sorry- C is 85%. My mistake 😡
I figured it out at the end- probability for all three tests to be positive is exactly what you wrote.
I'm bad in statistics. Hate it actually!