say something agreeing with "For my normal curve I have chosen TEST SCORES on exams. The mean determines where the peak of the curve is centered. Increasing the mean moves the curve right, while decreasing it moves the curve left. The standard deviation stretches or squeezes the curve. A small standard deviation results in a narrow curve, while a large standard deviation leads to a wide curve. - to + = 68% within the 1st standard deviation from the mean - 2 to + 2 = 95% within the 2nd standard deviation from the mean - 3 to + 3 = 99.7% within the 3rd standard deviation from the mean Exam test scores = 53 Population deviation = 15 Test score average between 5-100% Standard deviation 99.7%/2=49.9%