The weights of the fish in a certain lake are normally distributed with a mean of 18 lb and a standard deviation of 18 . if 15 fish are randomly selected, what is the probability that the mean weight will be between 16.6 and 21.6 lb?

0.3991

Step-by-step explanation:

Given that the weights of the fish in a certain lake are normally distributed with a mean of 18 lb and a standard deviation of 18 .

we know that when a sample is taken mean would be the same but std error would vary

when a sample of size 15 is taken we have

Standard error of sample =

the probability that the mean weight will be between 16.6 and 21.6 lb

So we get the required probability as

0.3991

the answer to this question is in the pic

5 x 14?

im new, sorry if this is wrong.

step-by-step explanation: