When parking a car in a downtown parking lot, drivers pay according to the number of hours or fraction thereof. The probability distribution of the number of hours cars are parked has been estimated as follows: X 1 2 3 4 5 6 7 8 P(X) 0.219 0.105 0.121 0.099 0.055 0.021 0.025 0.355 A. Mean = B. Standard Deviation = The cost of parking is 3.5 dollars per hour. Calculate the mean and standard deviation of the amount of revenue each car generates. A. Mean = B. Standard Deviation

Private nonprofit four-year colleges charge, on average, $26,375 per year in tuition and fees. The standard deviation is $6,685. Assume the distribution is normal. Let X be the cost for a randomly selected college. Round all answers to 4 decimal places where possible. a. What is the distribution of X? X - N( b. Find the probability that a randomly selected Private nonprofit four-year college will cost less than 24,855 per year. c. Find the 80th percentile for this distribution. $ (Round to the nearest dollar.)

Private nonprofit four-year colleges charge, on average, $26,168 per year in tuition and fees. The standard deviation is $6,656. Assume the distribution is normal. Let X be the cost for a randomly selected college. Round all answers to 4 decimal places where possible. a. What is the distribution of X? X - N( b. Find the probability that a randomly selected Private nonprofit four-year college will cost less than 24,347 per year. c. Find the 74th percentile for this distribution. $ (Round to the nearest dollar.)

Given a normal probability distribution with a mean of 9% and a standard deviation of 4%, what is the probability of observing a value between 2% and 14%? Use the following Z-score data is from the HP calculator: Z-Score -2.00 -1.75 -1.50 -1.25 -1.00 0.00 1.00 1.25 1.50 1.75 2.00 Probability 0.0228 0.0401 0.0668 0.1056 0.1587 0.5000 0.8413 0.8944 0.9332 0.9599 0.9772 Answer in decimal format, to 3 decimal places, truncated. For example, if your answer is 33.46%, enter 0.334.

Suppose a sample of O-rings was obtained and the wall thickness (in inches) of each was recorded. Use a normal probability plot to assess whether the sample data could have come from a population that is normally distributed. 0.163 0.182 0.194 0.211 0.224 0.225 0.233 0.243 0.251 0.259 0.271 0.273 0.295 0.307 0.317 0.340 Click here to view the table of critical values for normal probability plots. Click here to view page 1 of the standard normal distribution table. Click here to view page 2 of the standard normal distribution table. Using the correlation coefficient of the normal probability plot, is it reasonable to conclude that the population is normally distributed? Select the correct choice below and fill in the answer boxes within your choice. (Round to three decimal places as needed.) A. No. The correlation between the expected z-scores and the observed data, normal population. does not exceed the critical value, Therefore, it is not reasonable to conclude that the data come from…

Please also find the variance, standard deviation.

What is the probability of randomly selecting a z-score less than z = –1.25 from a normal distribution?​   Question options: a. ​0.2112 b. ​0.1056 c. ​0.8944 d. ​0.3944