SOLUTION: A study shows that scores on an aptitude test are normally distributed with a mean of 70 and a standard deviation of 12. Find the following probabilities:
a. If one test taker is
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-> SOLUTION: A study shows that scores on an aptitude test are normally distributed with a mean of 70 and a standard deviation of 12. Find the following probabilities:
a. If one test taker is
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Question 1161059: A study shows that scores on an aptitude test are normally distributed with a mean of 70 and a standard deviation of 12. Find the following probabilities:
a. If one test taker is selected, that the person scored greater than 75.
b. If 9 test takers are selected, that they have a mean score greater than 75. c. If 49 test takers are selected, that they have a mean score greater than 75.
You can put this solution on YOUR website! z=(x-mean)/sd
z > (5/12) with probability 0.3385
b. denominator is now sigma/sqrt (n), so z> (5/12/3) or z > 15/12 with probability 0.1056
c. z>35/12 with probability 0.0018
