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…

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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In a random sample of n=1000 families in the city of Portland, it is found that x=600families own at least two cars.(a) Find a 95% confidence interval for the actual proportion of families with at least twocars in this city. (b) If we want to claim with 95% confidence that our estimate of the percentage offamilies owning at least two cars in Portland is off the actual percentage by less than0.025, does the sampling provide sufficient supports for this claim? Why?
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I need help with the last three.
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