Posted by Sarah on Thursday, November 25, 2010 at 6:12am.
The weights of the fish in a certain lake are normally distributed with a mean of 11 lb and a
standard deviation of 6. If 4 fish are randomly selected, what is the probability that the mean
weight will be between 8.6 and 14.6 lb?
A) 0.0968 B) 0.4032 C) 0.3270 D) 0.6730

Statistics  PsyDAG, Thursday, November 25, 2010 at 10:28am
Z = (mean1  mean2)/standard error (SE) of difference between means
SEdiff = √(SEmean1^2 + SEmean2^2)
SEm = SD/√(n1)
If only one SD is provided, you can use just that to determine SEdiff.
Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportions related to the Z scores.

Statistics  Sarah, Sunday, November 28, 2010 at 3:55am
i still don't get how to do it?
Answer This Question
Related Questions
 stats  the weights of the fish in a certain lake are normally distributed with ...
 stats  so the question is: the weights of fish in a certain lake are normally ...
 Statistics  The weights of the fish in a certain lake are normally distributed ...
 statistics  An automatic machine that fills bags of unpopped popcorn is ...
 statistics  An automatic machine that fills bags of unpopped popcorn is ...
 math  Bass: The bass in Clear Lake have weights that are normally distributed ...
 Statistics  An engineer is going to redesign an ejection seat for an airplane. ...
 statistics  The weights of steers in a herd are distributed normally. The ...
 statistics  Individual M&M plain candies have weights that are normally ...
 math  Weights of women are normally distributed with mean 143 pounds and ...
More Related Questions