Which of the following formulas is used to calculate the standard deviation of the sampling distribution of the sample mean (for infinite population) when the population standard deviation is given? 5. N-n A. 0z N-n C. OR Vn+1 N-1 N-1 D. OE B. 0

Which of the following is true regarding the sampling distribution of the mean for a large sample size? O It has a normal distribution with the same mean and standard deviation as the population. O It has the same shape, mean, and standard deviation as the population. O It has the same shape and mean as the population, but has a smaller standard deviation. O It has a normal distribution with the same mean as the population but with a smaller standard deviation.

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Use the normal distribution of SAT critical reading scores for which the mean is 501501 and the standard deviation is 113113. Assume the variable x is normally distributed. left parenthesis a right parenthesis(a) What percent of the SAT verbal scores are less than 550550​? left parenthesis b right parenthesis(b) If 1000 SAT verbal scores are randomly​ selected, about how many would you expect to be greater than 525525​?

For the population proportion is… (select answer) Skewed right Uniform Approximately normal Skewed left With the… (select answer) True population proportion True population mean True population standard deviation As it’s… (select answer) Proportion Mean Standard deviation

The age of children in kindergarten on the first day of school is uniformly distributed between 4.88 and 5.8 years old. A first time kindergarten child is selected at random. Round answers to 4 decimal places if possible. a. The mean of this distribution is b. The standard deviation is c. The probability that the the child will be older than 5 years old? d. The probability that the child will be between 5.38 and 5.58 years old is e. If such a child is at the 40th percentile, how old is that child? years old.

The average THC content of marijuana sold on the street is 11%. Suppose the THC content is normally distributed with standard deviation of 1%. Let X be the THC content for a randomly selected bag of marijuana that is sold on the street. a. What is the distribution of X? X - N( 11 1 b. Find the probability that a randomly selected bag of marijuana sold on the street will have a THC content greater than 10.3. Round to 4 decimal places. c. Find the 77th percentile for this distribution. Round to 2 decimal places. %

What is the mean and standard deviation of the sampling distribution of X¯X¯ for n = 16, if the sampled population has a mean of 48 and a standard deviation of 12? Select one: a. 4 and 1 b. 12 and 3 c. 48 and 3 d. 48 and 1 e. 48 and 12

Ch 8 FRO The distribution of average speeds of the top 53 drivers in NASCAR is roughly symmetric, unimodal, and bell-shaped, with a mean of 184.8 mph and a standard deviation of 7.2 mph. In the space above, draw a Normal Curve, from z=-3 to z=+3. Draw vertical ines at the mean and each whole number standard deviation above and below the mean. Write two rows of numbers under the base line; one row with the number of standard deviations above and below the mean (z-scores), and a row under that with the actual values for this problem. What percent of drive would you expect to have speeds below 199.2 mph ? Show all work. What is the area under the curve to the left of a speed of 170.4mph ? Show all work.

Which is NOT a correct statement about the variance and standard deviation?   a. The standard deviation is the sqaure root of the variance   b. The standard deviation is useful when considering how close the data are to the mean   c. The variance is roughly the average sqaured distance from the mean   d. None of above