SOLUTION: Dr Carl is a mathematics and statistics lecturer. He is interested in studying a new approach at teaching mathematics and statistics in high school. Recently this new approach has

Question 221781: Dr Carl is a mathematics and statistics lecturer. He is interested in studying a new approach at teaching mathematics and statistics in high school. Recently this new approach has been adopted.
It was previously the case that the mean score for all high school students doing their end of year exam was 68, however, the population standard deviation is unknown. The scores of all students are approximately normally distributed.
He thinks that, with this new teaching approach, the mean score may have increased.
A random sample of 50 scores is gathered and the sample mean and standard deviation calculated.
Dr Carl will conduct a hypothesis test using a level of significance of 0.05.
Select the correct null and alternate hypotheses for this test:

a.)H0: μ > 68
H1: μ ≤ 68

b.)H0: μ ≤ 68
H1: μ < 68

c.)H0: μ = 68
H1: μ ≠ 68

d.)H0: μ ≤ 68
H1: μ > 68
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
d
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Cheers,
Stan H.
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