When reporting your confidence intervals, your answers should include a sentence with the basic form:

"We are ____% confident that the mean of _______________ is between ____ and _____.

1. A study measured the LDL cholesterol level in 49 subjects. The subjects were then treated with raw garlic for six months. The mean change in the 49 subjects was a reduction of 0.4 with a standard deviation of 21.0 (assume this is the actual standard deviation for the population, not and estimate). Find a 95% confidence interval for the mean change in LDL cholesterol after a treatment of garlic. Do you think garlic is effective in reducing LDL cholesterol?