2. Mr. Guo receives many spam emails each day. A random sample of12850 emails in his inbox indicates that 13 out of every 25 emails inhis inbox is spam.(a) Find a reasonable point estimate for p.(b) Mr. Guo wishes to find a 97% confidence interval for p. Are allconditions for the Large-Sample Confidence Interval met? If not,explain why.(c) Find the z critical number associated with a 97% confidence in-terval. Hint: We are looking for z such that the central area is97%.(d) Construct a central 97% confidence interval for p.(e) What is the minimum sample size required to conservatively es-timate Р within .005 with 97% confidence?

It is specified that for 12850 sampled emails (i.e., the sample size, n=12850), the no. of emails…

Answered: Mr. Guo receives many spam emails each…

Glencoe Algebra 1, Student Edition, 9780079039897, 0079039898, 2018

18th Edition

ISBN:9780079039897

Author:Carter

Publisher:Carter

Chapter4: Equations Of Linear Functions

Section: Chapter Questions

Problem 8SGR

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Suppose that a random sample of 11 adults has a mean score of 79 on a standardized personality test, with a standard deviation of 7 . (A higher score indicates a more personable participant.) If we assume that scores on this test are normally distributed, find a 90% confidence interval for the mean score of all takers of this test. Then find the lower limit and upper limit of the 90% confidence interval
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Let us suppose we have data on the absorbency of paper towels that were produced by two different manufacturing processes. From process 1, the sample size was 10 and had a mean and standard deviation of 190 and 15, respectively. From process 2, the sample size was 4 with a mean and standard deviation of 350 and 50, respectively. Find a 95% confidence interval on the difference in the towels' mean absorbency produced by the two processes. Assume the standard deviations are estimated from the data. Round your answers to two decimal places (e.g. 98.76). eTextbook and Media How would you interpret this CI? O The hypothesis test for the equality of means would not reject the null hypothesis (that the means do not differ) at a = 0.05. O The hypothesis test for the equality of means would reject the null hypothesis (that the means do not differ) at a = 0.05. eTextbook and Media Is the value zero in the Cl? O Yes, zero is contained in this interval. O No, zero is not contained in this…
Suppose that the average time spent per day with digital media several years ago was 3 hours and 27 minutes. For last year, a random sample of 20 adults in a certain region spent the numbers of hours per day with digital media given in the accompanying table. Preliminary data analyses indicate that the t-interval procedure can reasonably be applied. Find and interpret a 95% confidence interval for last year's mean time spent per day with digital media by adults of the region. (Note: x=5.45 hr and s=2.20 hr.) Click here to view the digital media times. LOADING... Click here to view page 1 of the t-table. LOADING... Click here to view page 2 of the t-table. LOADING... Question content area bottom Part 1 The 95% confidence interval is from enter your response here hour(s) to enter your response here hour(s). (Round to two decimal places as needed.) Part 2 Interpret the 95% confidence interval. Select all that apply. A. With 95% confidence, the mean…
Suppose a researcher is interested in the relationship between periodontal disease and a number of negative health outcomes. One outcome of particular interest to the researcher is hypertension (assume defined as systolic blood pressure above 140 mmHG). Suppose a team gathers a SRS of 348 participants with periodontal disease, and finds the sample average systolic blood pressure to be 157 mmHG. Using an assumed σ=16 mmHG Create a 95% confidence interval about the sample mean calculated by the research team, and interpret the interval.

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