Suppose you know σ and you want an 85% confidence level. what value would you use to multiply the standard error of the mean by? (round your answer to 2 decimal places.) value to multiply the standard error of the mean with

Go to the z table and find the z value associated with .075 The "trick" to using the z table is to look at the z score of "1". THAT will tell you what percentage they are reporting. If the % is 84%, they are reporting from the left tail to the value. If they report 34%, they are reporting from the mean to the score. The table I used reported 34% (.34), so it is reporting from the mean. NOW, I wish to find the z score such that 7.5% is to the "right" of that score. Thus, 42.5% must be to the LEFT of the z score. (i.e. 42.5% from the mean to the score.) Going to the table yields the number 1.44. Since the curve is symmetrical, the "left value" must be - 1.44