Question 1209960
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55% of all shark attacks are not fatal. Let r be the number of nonfatal attacks out of a random sample of five shark attacks. 
(a) What is the probability all five shark attacks are nonfatal?  
(b) What is the probability that three or more of the five shark attacks are nonfatal?  
(c) What is the expected number of nonfatal shark attacks out of the five? 
(d) What is the standard deviation of the r-probability distribution? 
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Be aware !


Calculations and the answer in the post by @CPhill in part (b) are INCORRECT.