Question 443068
Binomial probability: 
Jessie is a fantastic goalie who stops three out of every four penalty shots taken on her. 
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P(blocks shot) = 3/4 = 0.75
P(allows goal) = 0.25
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In a particularly tough game, she faced five penalty shots. What is the probability she lets only one of the five shots score?
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Binomial Problem with n = 5 and p = 0.25 (allows goal)
P(allows one goal in 5 shots) = 5C1(0.25)(0.75)^4 = 0.3955
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Comment: Get away from using the words "success" and "failure".
Use the words relating to the situation described. Actually
write the words down as I have above.  That way you will aways
know what p is and what q is.
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Cheers,
Stan H.