7-10

7. In a normal distribution, x = 3 and z = 0.67. This tells you that x = 3 is standard deviations to the (right or left) of the mean. 8. About what percent of the x values from a normal distribution lie within two standard deviations (left and right) of the mean of that distribution? 9. About what percent of x values lie between the mean and three standard deviations? 10. The patient recovery time from a particular surgical procedure is normally distributed with a mean of 5.3 days and a standard deviation of 2.1 days. What is the z-score for a patient who takes ten days to recover