A researcher is interested in finding a 90% confidence interval for the mean number of times perday that college students text. The study included 117 students who averaged 32.4 texts perday. The standard deviation was 13.8 texts. Round answers to 3 decimal places where possible.a. To compute the confidence interval use a ? distribution.b. With 90% confidence the population mean number of texts per day is betweentexts.andc. If many groups of 117 randomly selected members are studied, then a different confidenceinterval would be produced from each group. Aboutpercent of these confidenceintervals will contain the true population number of texts per day and aboutwill not contain the true population mean number of texts per day.percent

Solution: Given information: n= 117 Sample size x = 32.4 Sample mean s= 13.8 Sample standard…

Answered: A researcher is interested in finding a…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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Suppose that the average gregariousness score for the entire U.S. population is 70. The head research psychologist at Somerville University is interested in determining whether or not the university psychology students are statistically significantly more gregarious than the overall population. A random sample of 200 students from Somerville University shows a mean of 75 on the gregarious test with a sample standard deviation of 20. a. State the research hypothesis. b. State the null hypothesis. c. Identify the test statistic and provide the formula.
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Suppose that the number of points scored in a game comes from a normal population with an average of 12 points and a standard deviation of 9 points. Estimate the chance that the average points scored in ten randomly selected games will exceed 14.2 points. A. 0.4034 B. 0.0073 C. 0.2198 D. 0.2297
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1) The mean and standard deviation of a population are 200 and 20, respectively.The probability of selecting one data value less than 190 is ____ %. (Round answer to the nearest percent (whole number). Do not write the % sign.) 2) A. C. Neilsen reported that children between the ages of 2 and 5 watch an average of 25 hours of television per week. Assume the variable is normally distributed and the standard deviation is 3 hours.If 20 children between the ages of 2 and 5 are randomly selected, the number of children in the sample who watch at least 25.2 hours of television is? Give answer to the nearest whole number, not a percent. 3) A. C. Neilsen reported that children between the ages of 2 and 5 watch an average of 25 hours of television per week. Assume the variable is normally distributed and the standard deviation is 3 hours.If 20 children between the ages of 2 and 5 are randomly selected, the number of children in the sample who watch at most 22.5 hours of television is? . Give…
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