1 Before this year a large college of nursing had an average

#1) Before this year, a large college of nursing had an average student score of 81.5 on the state licensing exam. This year, the college made some changes in the curriculum and exam preparation in the hopes that exam scores would improve. To see if scores have improved, a random sample of 40 students was selected. The sample mean exam score was 82.6 with sample standard deviation 7.1. Does this sample data indicate that the population mean score on the exam has improved? Use a 5% significance level to test. The correct hypotheses for this test are

H_O: mu = 81.5

H_A: mu \"not=\" 81.5

H_O:  mu = 81.5

H_A:  mu < 81.5

H_O: mu = 81.5

H_A: mu > 81.5

H_O: mu = 82.6

H_A: mu = 81.5

#2) Before this year, a large college of nursing had an average student score of 81.5 on the state licensing exam. This year, the college made some changes in the curriculum and exam preparation in the hopes that exam scores would improve. To see if scores have improved, a random sample of 40 students was selected. The sample mean exam score was 82.6 with sample standard deviation 7.1. Does this sample data indicate that the population mean score on the exam has improved? Use a 5% significance level to test. Using the correct test, the p-value is

.12

.14

.15

.17

3)

Before this year, a large college of nursing had an average student score of 81.5 on the state licensing exam. This year, the college made some changes in the curriculum and exam preparation in the hopes that exam scores would improve. To see if scores have improved, a random sample of 40 students was selected. The sample mean exam score was 82.6 with sample standard deviation 7.1. Does this sample data indicate that the population mean score on the exam has improved? Use a 5% significance level to test. The correct conclusion is

reject H_O, population mean exam score has improved (is greater than 81.5) since the changes

reject H_O, so population mean exam score must still be 81.5 since the changes

fail to reject H_O, there is not enough evidence to say the population mean exam score has improved (is greater than 81.5) since the changes

fail to reject H_O, the population mean exam score must still be 81.5 since the changes

Solution

1.

Formulating the null and alternative hypotheses,              
              
Ho:   u   =   81.5  
Ha:    u   >   81.5   [ANSWER, OPTION C]

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2.
              
As we can see, this is a    right   tailed test.      
              
              
Getting the test statistic, as              
              
X = sample mean =    82.6          
uo = hypothesized mean =    81.5          
n = sample size =    40          
s = standard deviation =    7.1          
              
Thus, z = (X - uo) * sqrt(n) / s =    0.979860683          
              
Also, the p value is              
              
p =    0.163577446

The closest answer is p = 0.17 [ANSWER, D]

Note: There could be some round off errors in your instructor\'s solution, that\'s why the discrepancy.

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3.           
              
As P > 0.05,

OPTION C: fail to reject HO, there is not enough evidence to say the population mean exam score has improved (is greater than 81.5) since the changes   [ANSWER]