Divide by the square root of the sample size in this case since the problem is looking to find the probability for the sample mean.
20 - 20.21 / .12/√24 -->note the sample size is 24.
I hope this will help.
Assume 20 oz. cola bottles are filled so that the mean amount of liquid contained in the bottle is 20 oz and the standard deviation is .12 oz. If a case of 24 bottles is randomly selected from the population of all soda bottles, find the probability that the mean number of ounces in each bottle in the sample is above 20.21 (i.e., find the probability for the sample mean).
I'm a little lost. Here's what I have so far:
24 - 20.21 / .12
3.79 / .12 = 31.5833
I'm positive I've already taken a wrong turn somewhere because I'm pretty sure my z-score shouldn't be so high...
1 answer
5 answers