Question

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Grade inflation In 1996, 20% of all students at a major university had an overall grade point average of 3.5 or higher (on a scale of 4.0). In 2012, a random sample of 1100 student records found that 25% had a GPA of 3.5 or higher. Is this evidence of grade inflation?

Answer 1

Here, lhe have na 1100 | 0 - 0,25 Stephir Hypothesis 1. Ho: P2 0.20 1. Ha:p> 0:20 This is a right tailed test steppir Pest stahi hics Z= - P = 0.24-0.20 "n 4 1 0 0 [4.15] Step 3: Pualue Pvalue at 2:14.151 Pravie - PLZ >4.15) 1- PIZ<4:15) 21 - 0.999983 Ifrom standard 3:0.000017 10.00001 Round to a decimal normal Calculator plach.

Step 4:- Decision Since Pralie <10.05) (Assumed), 80 reject the S null Hypothesis, Step si conclusion Rejects the nul Hypothesis and there is sufficient evidence to support the claim about grade inflation,