Question 909965: The average grade point average (GPA) of undergraduate students in New York is normally distributed with a population mean of 2.5 and a population standard deviation of 0.4. Compute the following, showing all work:
1) The percentage of students with GPA's between 2.0 and 2.6
2) The percentage of students with GPA's below 2.7
3) Above what GPA will the top 7% of the students be(i.e., compute the 93rd percentile)
4) If a sample of 49 students is taken, what is the probability that the sample mean GPA will be between 2.60 and 2.70?
Answer by ewatrrr(24785) (Show Source):
You can put this solution on YOUR website! m = 2.5, sd = .4
1) normalcdf(2.0,2.6,2.5,.4)
2) normalcdf(-10,2.7,2.5,.4)
3) .4invNorm(.93) + 2.5 = X
4 t1 = (.1/(.4/sqrt(49)) and t2 = (.2/(.4/sqrt(49))
P(t2< value) - P(t1< value)
Use df = 48
tcdf(-100,3.5 , 48) - tcdf(-100,1.75 , 48)
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