a) Z = (score-mean)/SD
Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability related to the Z score.
b) Z = (score-mean)/SEm
SEm = SD/√n
Use same table.
Bottles of a popular cola contain a mean amount of 300 mL of cola. There is some variation from bottle to bottle because the filling machinery is not perfectly precise. The distribution of the contents is normal with a standard deviation of 3 mL.
a) What is the probability that one randomly selected bottle will contain less than
296 mL of cola?
b) What is the probability that the average of 6 randomly selected bottles will contain less than 296 mL of cola?.
1 answer