4157 . '5' C} G myopenmath.com 6.1 The Empirical Rule 68-95-99] According to National Testing data, college math class testing times are Normally distributed with a mean of 42 minutes and standard deviation 8 minutes. The bell curve below represents the probability distribution for testing times. The scale on the horizontal axis is equal to the standard deviation. Fill in the three indicated boxes. Hint: The middle number represents the mean and the outer values are 2 standard deviations away from the mean. > Next Question 4157 . '5' C} G myopenmath.com 7.3 Central Limit Theorem: Finding Probability G Let X represent the full height of a certain species of tree. Assume that X has a normal probability distribution with mean 66.9 ft and standard deviation 88.9 ft. You intend to measure a random sample of n = 18 trees. The bell curve below represents the distribution of these sample means. The scale on the horizontal axis is the standard error (standard deviation) of the sampling distribution. Complete the indicated boxes, correct to two decimal places. t HI || 0'53: Hint: The middle number represents the mean and the outer values are 2 standard deviations away from the mean. > Next Question 4157 . "5' [3' G myopenmath.com E41 pt '0 1 Q) Details (9 6.2 The Standard Normal Distribution Table: Z-score and Probability A company produces steel rods. The lengths of the steel rods are normally distributed with a mean of 217.4 cm and a standard deviation of 1 cm. Find the probability that the length of a randomly selected steel rod is greater than 214.7 cm. Probability = [3 (Use 4 decimal places) > Next