3. A psychologist has been studying eye fatigue using a particular measure, which she administers to students after they have worked for 1 hour writing on a computer. Using the normal curve, what proportion of students have z-scores:

Below 1.2: P(Z<1.2) = 0.11507

Above 1.2: P(Z>1.2) = 0.88493

Below -.68: P(Z<-0.68) = 0.24825

Above -.68: P(Z>-0.68) = 0.75175

4. Using the example from above (question 3), suppose the test of eye fatigue had a mean of 15 ( =15), and a standard deviation of 5 (=5). Using the normal curve, what proportion of students have scores: Remember to convert the raw scores to z-scores first.

Below 16: (16-15)/5=.2 = 0.5793

Above 17: (17-15)/5=.4 = 1 - 0.65542= 0.3446

Below 18: (18-15)/5=.6 = 0.7257

Above 14: (14-15)/5=-.2 = 1 - 0.5793= .4207

5. Using the example from above (questions 3 and 4) and using the normal curve, what:

Does someone have to score to be in the 95^th percentile:_____________

Does someone have to score to be in the 80^th percentile:_____________

Does someone have to score to be in the 10^th percentile: _____________

Percentage of scores fall between the z-scores of -.60 and .60: ___________

Percentage of people have scores between 10 - 20 (M = 15, SD = 5): ________________