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by melony 1415 days ago
How do you get 18.6%?
1 comments
prirun 1415 days ago
Prob of no failure in 1 drive is 95%. Prob of no failure in 4 drives is .95^4 = .816. Prob of failure in any of 4 drives is 1-.816 = 18.6%

Disclaimer: I got a D in Probability & Statistics

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