A random sample of 81 eighth grade students' scores on a national mathematics assessment test has a mean score of 275. This test result prompts a state school administrator to declare that the mean score for the state's eighth graders on this exam is more than 270. Assume that the population standard deviation is 34. At a = 0.07, is there enough evidence to support the administrator's claim? Complete parts (a) through (e). (a) Write the claim mathematically and identify Ho and Ha. Choose the correct answer below. O A. Ho: u= 270 (claim) HiH>270 O B. Ho: u2 270 (claim) H:u<270 OC. Ho: us270 (claim) H: u> 270 O D. Ho: u<270 Ha:u2 270 (claim) Ο Ε. H ,: με 270 OF Hρ; μ5 270 Haiu> 270 (claim) H:u> 270 (claim) (b) Find the standardized test statistic z, and its corresponding area. z=O (Round to two decimal places as needed.) (c) Find the P-value. P-value = (Round to three decimal places as needed.) (d) Decide whether to reject or fail to reject the null hypothesis. O Fail to reject Ho O Reject Ho (e) Interpret your decision in the context of the original claim. At the 7% significance level, there V enough evidence to the administrator's claim that the mean score for the state's eighth graders on the exam is more than 270.

A nationwide test taken by high school sophomores and juniors has three sections, each scored on a scale of 20 to 80. In a recent year, the national mean score for the writing section was 50.4with a standard deviation of 9.1 a. According to Chebyshev's theorem at least ? of the score lies between 3.2 and 68.6 b. According to Chebyshev's theorem at least 56% of the fares lies between ? and ? (Round your answer to 2 decimal places.)

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For a data set of the pulse rates for a sample of adult females, the lowest pulse rate is 39 beats per minute, the mean of the listed pulse rates isx= 78.0 beats per minute, and their standard deviation is s = 20.7 beats per minute. a. What is the difference between the pulse rate of 39 beats per minute and the mean pulse rate of the females? b. How many standard deviations is that [the difference found in part (a)]? c. Convert the pulse rate of 39 beats per minutes to a z score. d. If we consider pulse rates that convert to z scores between - 2 and 2 to be neither significantly low nor significantly high, significant? the pulse rate of 39 beats per minute a. The difference is beats per minute. (Type an integer or a decimal. Do not round.) b. The difference is standard deviations. (Round to two decimal places as needed.) c. The z score is z = (Round to two decimal places as needed.) d. The lowest pulse rate is

Researchers measured the data speeds for a particular smartphone carrier at 50 airports. The highest speed measured was 77.3 Mbps. The complete list of 50 data speeds has a mean of x = 18.24 Mbps and a standard deviation of s = 17.77 Mbps. a. What is the difference between carrier's highest data speed and the mean of all 50 data speeds? b. How many standard deviations is that [the difference found in part (a)]? c. Convert the carrier's highest data speed to a z score. d. If we consider data speeds that convert to z scores between -2 and 2 to be neither significantly low nor significantly high, is the carrier's highest data speed significant? a. The difference is (Type an integer or a Mbps. decimal. Do not round.) b. The difference is (Round to two decimal standard deviations. places as needed.) c. The z score is z = (Round to two decimal places as needed.) d. The carrier's highest data speed is C

A random sample of 88 eighth grade students' scores on a national mathematics assessment test has a mean score of 281. This test result prompts a state school administrator to declare that the mean score for the state's eighth graders on this exam is more than 275. Assume that the population standard deviation is 40. At a = 0.03, is there enough evidence to support the administrator's claim? Complete parts (a) through (e). ..... (a) Write the claim mathematically and identify H, and Ha. Choose the correct answer below. ' O A. Ho: µs 275 Hai H> 275 (claim) B. H0: μ 275 c. Ho: μ 275 Ο Ε. Ho: μ = 275 Ha: µ> 275 (claim) OF H : μ2 275 (claim) Ha: µ<275

Researchers measured the data speeds for a particular smartphone carrier at 50 airports. The highest speed measured was 71.9 Mbps. The complete list of 50 data speeds has a mean of x 17.38 Mbps and a standard deviation of s = 19.81 Mbps. a. What is the difference between carrier's highest data speed and the mean of all 50 data speeds? b. How many standard deviations is that [the difference found in part (a))? c. Convert the carrier's highest data speed to a z score. d. If we consider data speeds that convert to z scores between -2 and 2 to be neither significantly low nor significantly high, is the carrier's highest data speed significant?

Use z scores to compare the given values. The tallest living man at one time had a height of 238 cm. The shortest living man at that time had a height of 142.4 cm. Heights of men at that time had a mean of 175.45 cm and a standard deviation of 5.59 cm. Which of these two men had the height that was more extreme? ... Since the z score for the tallest man is z = 0 and the z score for the shortest man is z = the man had the height that was Im- more extreme. (Round to two decimal places.) shortest tallest

Researchers measured the data speeds for a particular smartphone carrier at 50 airports. The highest speed measured was 72.6 Mbps. The complete list of 50 data speeds has a mean of x=18.29 Mbps and a standard deviation of s=19.75 Mbps.   a. What is the difference between​ carrier's highest data speed and the mean of all 50 data​ speeds? b. How many standard deviations is that​ [the difference found in part​ (a)]? c. Convert the​ carrier's highest data speed to a z score. d. If we consider data speeds that convert to z scores between −2 and 2 to be neither significantly low nor significantly​ high, is the​ carrier's highest data speed​ significant?       Question content area bottom Part 1 a. The difference is 54.3154.31 Mbps. ​(Type an integer or a decimal. Do not​ round.) Part 2 b. The difference is enter your response here standard deviations. ​(Round to two decimal places as​ needed.)