Example 2.1.3 A teacher conducted a study to know if blended learning affects the students' performances. A class of 30 students of Grade 11 was surveyed and found out that their mean score was 83 with a standard deviation of 4. A study from other country revealed that / 80 with a standard deviation of 3. Test the hypothesis at 0.10 level of significance. Solution: Given: sample size n=30 Parameter: population mean , 80 population standard deviation o=3 Statistic: sample mean x =83 Step 1. Formulation of null and alternative hypotheses. H: The mean score of students' performances in blended learning is 80. In symbol, H : # 80 H : The mean score of students' performances in blended learning is greater than 80 In symbol, H : >80 (We used greater than because sample mean 83 is greater than population mean 80.)