When transforming a normal distribution to the standard normal distribution, what changes? The shape of the...
Describe how the shape and standard deviation of a sampling distribution changes as sample size increases. In other words, describe the changes that occur to a sampling distribution according to the Central Limit Theorem. Make sure you describe what a sampling distribution is in your answer. Generate pictures/diagrams to illustrate your thoughts if you would like.
The location of a Normal distribution is determined by its mean μ, where as its shape is determined by the standard deviation σ. To see the effect of changing μ, you are going to graph two Normal probability density functions, one with μ = 100 and another with μ = 105, both having σ = 10. Recall that for each distribution the first value should be 3σ = 30 below the mean, and the last value should be 3σ above...
Given a normal distribution with (mean) μ= 50 and (standard deviation) σ = 5, what is the probability that: a) X>60 b) X<40 c) X<45 or X>65 d) Between what two values (symmetrically distributed around the mean) are ninety percent of the values?
The distribution of IQ (Intelligence Quotient) is approximately normal in shape with a mean of 100 and a standard deviation of 20. According to the standard deviation rule, only % of people have an IQ over 160.
The distribution of IQ (Intelligence Quotient) is approximately normal in shape with a mean of 100 and a standard deviation of 14. According to the standard deviation rule, 128. Do not round. % of people have an IQ between 72 and
The shape of the distribution of the time required to get an oil change at a 10-minute oil change facility is unknown. However, records indicate that the mean time is 11.1 minutes, and the standard deviation is 4.4 minutes. Complete parts (a) through (c). (a) To compute probabilities regarding the sample mean using the normal model, what size sample would be required? A. The sample size needs to be less than or equal to 30. B. The sample size needs...
27. On a standardized test with a normal distribution, the mean was 64.3 and the standard deviation was 5.4. What is the best approximation of the percent of scores that fell between 61.6 and 75.1? 28. The mean of a normally distributed set of data is 52 and the standard deviation is 4. Approximately 95% of all the cases will lie between which measures? 29. Battery lifetime is normally distributed for large samples. The mean lifetime is 500 days and...
In a normal distribution with mean 3 and standard deviation of 7, what are the upper and lower limit x values for the middle 50% of the data?
7. Determine whether a normal distribution or a normal distribution or t distribution should be used or whether neither of should be used to construct a confidence interval for the mean. (Section 6.2) Circle the correct answer. in a random sample of 22 families, the mean weekly food expense was $95.60 with a sample standard deviation of $22.50. Assume the weekly food expense is normally distributed. A) Normal distribution B) t-distribution C) Neither For a sample of 20 IQ scores...
Question 3: Consider the Standard Normal Distribution with mean 0 and standard deviation 1. Find the following. a) P (z>0.5) b) P(z 1.5) c) P (-0.49 < z1.5) Question 4: If you have a normal distribution with mean 14 and standard deviation of 2. What is P(x >16)? Question 5 Professor Hardy assumes the exam scores are normally distributed and wants to grade "on a curve." The mean score was 68, with a standard deviation of 9, If he wants...