Many rms use on-the-job training to teach their employees computer programming. Suppose you work in the personnel department of a rm that just nished training a group of its employees to program, and you have been requested to review the performance of one of the trainees on the nal test that was given to all trainees. The mean and standard deviation of the test scores are 73 and 3, respectively, and the distribution of scores is bell-shaped and symmetric. Suppose the trainee in question received a score of 65. Compute the trainee's zscore. <:> A. z=-0.85 O B. z=2.67 0C. z=-2.67 O D. z=0.85 The heights of fully grown trees of a specific species are normally distributed, with a mean of 72.5 feet and a standard deviation of 7.25 feet. Random samples of size 17 are drawn from the population. Use the central limit theorem to find the mean and standard error of the sampling distribution. Then sketch a graph of the sampling distribution. . . . The mean of the sampling distribution is us = The standard error of the sampling distribution is of = (Round to two decimal places as needed.) Choose the correct graph of the sampling distribution below. O A. O B. O C. + + + .X X XI 2 69.0 72.5 76.0 58.0 72.5 87.0The population mean and standard deviation are given below. Find the required probability and determine whether the given sample mean would be considered unusual. For a sample of n = 65, nd the probability of a sample mean being greater than 215 if p = 214 and o = 5.7. For a sample of n = 65, the probability of a sample mean being greater than 215 if p = 214 and o = 5.7 is D. (Round to four decimal places as needed.) Would the given sample mean be considered unusual? The sample mean be considered unusual because it |:l within the range of a usual event, namely within of the mean of the sample means. The scores on a mathematics exam have a mean of 79 and a standard deviation of 6. Find the xvalue that corresponds to the z-score - 1.96. Round the answer to the nearest tenth. <:> O A. 90.8 0 B. 73.0 0 C. 77.0 0 D. 67.2 The lengths of lumber a machine cuts are normally distributed with a mean of 97 inches and a standard deviation of 0.4 inch. (a) What is the probability that a randomly selected board cut by the machine has a length greater than 97.14 inches? (b) A sample of 43 boards is randomly selected. What is the probability that their mean length is greater than 97.14 inches? <:> (a) The probability is D. (Round to four decimal places as needed.) (b) The probability is D. (Round to four decimal places as needed.) The mean SAT verbal score is 483, with a standard deviation of 99. Use the empirical rule to determine what percent of the scores lie between 483 and 681. (Assume the data set has a bell-shaped distribution.) E) O A. 68% O B. 47.5% 0 C. 34% D. 49.9% Assume that females have pulse rates that are normally distributed with a mean of p = 75.0 beats per minute and a standard deviation of o = 12.5 beats per minute. Complete parts (a) through (0) below. E) a. If 1 adult female is randomly selected, find the probability that her pulse rate is between 69 beats per minute and 81 beats per minute. The probability is D. (Round to four decimal places as needed.) b. If 16 adult females are randomly selected, nd the probability that they have pulse rates with a mean between 69 beats per minute and 81 beats per minute. The probability is D. (Round to four decimal places as needed.) c. Why can the normal distribution be used in part (b), even though the sample size does not exceed 30? O A. Since the original population has a normal distribution, the distribution of sample means is a normal distribution for any sample size. 0 B. Since the distribution is of sample means, not individuals, the distribution is a normal distribution for any sample size. 0 G. Since the mean pulse rate exceeds 30, the distribution of sample means is a normal distribution for any sample size. 0 D. Since the distribution is of individuals, not sample means, the distribution is a normal distribution for any sample size. The mean score of a competency test is 76, with a standard deviation of 6. Use the empirical rule to find the percentage of scores between 58 and 94. (Assume the data set has a bell-shaped distribution.) . . O A. 68% O B. 50% O C. 99.7% O D. 95%Find the area of the indicated region under the standard normal curve. .1 .13 o 2.03 E> O A. 0.8489 0 B. 0.1292 0 C. 0.1504 0 D. 0.0212 The monthly utility bills in a city are normally distributed, with a mean of $100 and a standard deviation of $14. Find the probability that a randomly selected utility bill is (a) less than $70, (b) between $86 and $120, and (c) more than $150. E> (a) The probability that a randomly selected utility bill is less than $70 is D. (Round to four decimal places as needed.) (b) The probability that a randomly selected utility bill is between $86 and $120 is El. (Round to four decimal places as needed.) (0) The probability that a randomly selected utility bill is more than $150 is El. (Round to four decimal places as needed.) The mean percent of childhood asthma prevalence in 43 cities is 2.27%. A random sample of 32 of these cities is selected. What is the probability that the mean childhood asthma prevalence for the sample is greater than 2.5%? Interpret this probability. Assume that 5 = 1 20%. E) The probability is D. (Round to four decimal places as needed.) Interpret this probability. Select the correct choice below and ll in the answer box to complete your choice. (Round to two decimal places as needed.) 0 A- About |:|% of samples of 32 cities will have a mean childhood asthma prevalence greater than 2.5%. O B- About |:|% of samples of 43 cities will have a mean childhood asthma prevalence greater than 2.5%. O c- About |:|% of samples of 32 cities will have a mean childhood asthma prevalence greater than 2.27%. A standardized exam's scores are normally distributed. In a recent year, the mean test score was 1505 and the standard deviation was 314. The test scores of four students selected at random are 1900, 1260, 2240, and 1390. Find the z-scores that correspond to each value and determine whether any of the values are unusual. <:> The z-score for 1900 is D. (Round to two decimal places as needed.) The z-score for 1260 is D. (Round to two decimal places as needed.) The z-score for 2240 is D. (Round to two decimal places as needed.) The z-score for 1390 is D. (Round to two decimal places as needed.) Which values, if any, are unusual? Select the correct choice below and, if necessary, ll in the answer box within your choice. 0 A- The unusual value(s) isfare El. (Use a comma to separate answers as needed.) 0 B. None of the values are unusual