SOLUTION: 20 % of all pregnancies are classifield as premature. What is the probability that between 17% and 22% of 100 randomly selected pregnancies are classified as premature?

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Question 418744: 20 % of all pregnancies are classifield as premature. What is the probability that between 17% and 22% of 100 randomly selected pregnancies are classified as premature?
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

 Note: The probability of x successes in n trials is: 

P = nCx* p%5Ex%2Aq%5E%28n-x%29 where p and q are the probabilities of success and failure 

respectively. In this case p = .20 and q = .80

nCx = n%21%2F%28x%21%28n-x%29%21%29  n =100

probability that between 17% and 22% of 100 randomly selected pregnancies are classified as premature?

P( >22)  - P(<17) = .8077 - .1923 = .6154