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Standard Normal Distribution. In Exercises 17–36, assume that a randomly selected subject is given a bone density test. Those test scores are
24. Greater than −3.05
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- Heart rate during laughter. Laughter is often called “the best medicine,” since studies have shown that laughter can reduce muscle tension and increase oxygenation of the blood. In the International Journal of Obesity (Jan. 2007), researchers at Vanderbilt University investigated the physiological changes that accompany laughter. Ninety subjects (18–34 years old) watched film clips designed to evoke laughter. During the laughing period, the researchers measured the heart rate (beats per minute) of each subject, with the following summary results: Mean = 73.5, Standard Deviation = 6. n=90 (we can treat this as a large sample and use z) It is well known that the mean resting heart rate of adults is 71 beats per minute. Based on the research on laughter and heart rate, we would expect subjects to have a higher heart beat rate while laughing.Construct 95% Confidence interval using z value. What is the lower bound of CI? a) Calculate the value of the test statistic.(z*) b) If…arrow_forwardComplete the table below and find the variance and standard deviation of the ff. probability distribution. (Answer should be in yellow pad.) V. ASSESSMENT 1. x•P(x) X2•P(x) P(x) 3/10 10 2/10 2/10 2/10 4 25arrow_forwardFind mean and standard deviation if n and p are 10 and 0.2 respectively.arrow_forward
- Constructing Normal Quantile Plots. In Exercises 17–20, use the given data values to identify the corresponding z scores that are used for a normal quantile plot, then identify the coordinates of each point in the normal quantile plot. Construct the normal quantile plot, then determine whether the data appear to be from a population with a normal distribution. Brain Volumes A sample of human brain volumes (cm3) is obtained from those listed in Data Set 8 “IQ and Brain Size” in Appendix B: 1027, 1029, 1034, 1070, 1079, 1079, 963, 1439.arrow_forwardDerive the mean and variance of the t distribution.arrow_forwardAssume that adults have IQ scores that are normally distributed with a mean of µ = 105 and a standard deviation o=15. Find the probability that a randomly selected adult has an IQ less than 129. Click to view page 1 of the table. Click to view page 2 of the table. 0 The probability that a randomly selected adult has an IQ less than 129 is (Type an integer or decimal rounded to four decimal places as needed.) 29 14 8 F5 ► 11 % F6 A F7 & F8 00 = F9 * F10 √ F11 O (1,0) F12 T More PrtScr (8") + Insert Delete Rackspace PgUp Num Lock Next PgDn X Homearrow_forward
- Does the Normal Probability plot look linear and do we use the t-procedure?arrow_forwardK Assume that adults have IQ scores that are normally distributed with a mean of μ= 105 and a standard deviation o=15. Find the probability that a randomly selected adult has an IQ less than 126. Click to view page 1 of the table. Click to view page 2 of the table. The probability that a randomly selected adult has an IQ less than 126 is (Type an integer or decimal rounded to four decimal places as needed.)arrow_forwardQ6- Assume the probability that a maple tree at age 5 grows less than 140 cm is equal to 0.2. If the height of maple trees at age 5 are estimated to be normally distributed with mean ? cm and variance 81 cm. find ?.arrow_forward
- We have provided a normal probability plot of data from a sample of a population. In each case, assess the normality of the variable under consideration.arrow_forwardK Assume that adults have IQ scores that are normally distributed with a mean of μ = 105 and a standard deviation o=20. Find the probability that a randomly selected adult has an IQ between 89 and 121. Click to view page 1 of the table. Click to view page 2 of the table. The probability that a randomly selected adult has an IQ between 89 and 121 is (Type an integer or decimal rounded to four decimal places as needed.)arrow_forwardResearch suggested that the distribution of amount of dissolved solids (D) at wastewater treatment plant is lognormal distribution with mean value 10260 kg/day/km and a coefficient of variation of 40 %. 1. What is the probability that D is at most 15050 kg/day/km? 2. What is the probability that Dexceeds the mean of the distribution? Is it 50%? Why/Why not? Note. Provide final solution for each questions below. Detailed solution to be uploaded.arrow_forward
- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw HillBig Ideas Math A Bridge To Success Algebra 1: Stu...AlgebraISBN:9781680331141Author:HOUGHTON MIFFLIN HARCOURTPublisher:Houghton Mifflin Harcourt