Scores for a common standardized college aptitude test are normally distributed with a mean of 499 and a standard deviation of 111. Randomly selected men are given a Prepartion Course before taking this test. Assume, for sake of argument, that the Preparation Course has no effect on people's test scores.
If 1 of the men is randomly selected, find the probability that his score is at least 552.5.
P(X > 552.5) =
Enter your answer as a number accurate to 4 decimal places.
If 19 of the men are randomly selected, find the probability that their mean score is at least 552.5.
P(x-bar > 552.5) =
Enter your answer as a number accurate to 4 decimal places.
If the random sample of 19 men does result in a mean score of 552.5, is there strong evidence to support a claim that the Preapartion Course is actually effective? (Use the criteria that "unusual" events have a probability of less than 5%.)
If 1 of the men is randomly selected, find the probability that his score is at least 552.5.
P(X > 552.5) =
Enter your answer as a number accurate to 4 decimal places.
If 19 of the men are randomly selected, find the probability that their mean score is at least 552.5.
P(x-bar > 552.5) =
Enter your answer as a number accurate to 4 decimal places.
If the random sample of 19 men does result in a mean score of 552.5, is there strong evidence to support a claim that the Preapartion Course is actually effective? (Use the criteria that "unusual" events have a probability of less than 5%.)