Probability and normal distribution : key information

1. At a computer manufacturing company, the actual size of computer chips is normally distributed with a mean of 1 centimeter and a standard deviation of 0.1 centimeter. A random sample of 12 computer chips is taken. What is the standard error for the sample mean?
a) 0.029
b) 0.050
c) 0.091
d) 0.120

2. The owner of a fish market has an assistant who has determined that the weights of catfish are normally distributed, with mean of 3.2 pounds and standard deviation of 0.8 pound. If a sample of 25 fish yields a mean of 3.6 pounds, what is the Z-score for this observation?
a) 18.750
b) 2.500
c) 1.875
d) 0.750

3. The owner of a fish market has an assistant who has determined that the weights of catfish are normally distributed, with mean of 3.2 pounds and standard deviation of 0.8 pound. If a sample of 16 fish is taken, what would the standard error of the mean weight equal?
a) 0.003
b) 0.050
c) 0.200
d) 0.800

Solution Summary

The solution solves the questions on probability and normal distributions.

... Generally the profits take normal distribution with the expected ... The probabilities shown above represent the states of ... ΣPi*Xi Where Pi=Probability of state of ...

... The package delivery time is approximately Normal** with mean ... we can use the above probabilities to calculate ... Note: The expected frequencies=probability*100. ...

... Notice that the sum of the probabilities of all ... under the curve represents the probability of the ... 68% of the observations in a normal distribution fall within ...

... are: Example: Uniform probability distribution over the ...key continuous distributions normal, uniform, exponential. Found probabilities using formulas and tables. ...

...Probability Density Function (pdf) with mean µ , standard deviation ... 8 normal variates with ... 1.749878 > # z-values for some common probabilities > qnorm(seq ...

... to draw both the null and alternative distributions of the ... the alternative is that of a normal distribution with mean ... every sample size n, the probability of a ...

...Key: 8j1 = 81 18 1 1 1 1 8 6 6 6 9 ... Tc=TINV(0.02, 21) (0.02 is the probability, 21 is the ... mean that you would get if you incorrectly used a normal distribution. ...

... is important to use a normal distribution for all ... important to develop a cumulative probability distribution C. It ... not important to assign probabilities to an ...

... In this context, the p value represents the probability that the sample test ... Then x has a distribution that is approximately normal with population mean ...