14) Arsenic is an element that can naturally get into local water supplies. The maximum safe level of arsenic in water is assumed to be 10 parts per billion (ppb). A sample of n=35 homes were sampled for tap water, and the sample mean arsenic level was found to be 9.72 ppm. If the population standard deviation is assumed to be 0.55 ppb, then: (a) write the null and alternate hypotheses to test to see if the mean concentration of arsenic in tap water is less than 10 ppb; b) Carry out a one-sample z-test at the 5% significance level Instead of a z-test, repeat this test using the p-value approach. All you need to do is calculate the p-value. Then state whether you would accept or reject the null hypothesis at the 5% level based on the p-value. No need to re-write everything else.

14) Arsenic is an element that can naturally get into local water supplies. The maximum safe level of arsenic in water is assumed to be 10 parts per billion (ppb). A sample of n=35 homes were sampled for tap water, and the sample mean arsenic level was found to be 9.72 ppm. If the population standard deviation is assumed to be 0.55 ppb, then: (a) write the null and alternate hypotheses to test to see if the mean concentration of arsenic in tap water is less than 10 ppb; b) Carry out a one-sample z-test at the 5% significance level Instead of a z-test, repeat this test using the p-value approach. All you need to do is calculate the p-value. Then state whether you would accept or reject the null hypothesis at the 5% level based on the p-value. No need to re-write everything else.

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Description: 10:05 AM Sat Dec 19* 64%+: 014) Arsenic is an element that can naturally get into local water supplies. The maximum safelevel of arsenic in water is assumed to be 10 parts per billion (ppb). A sample of n = 35homes were sampled for tap water, and th

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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. The acceptable pollutant level in a county is 7.8 g/cc. A researcher believes that their portion of the county has a level higher than this, and takes a sample of 70 observations. The sample mean is 8.8 g/cc, with a standard deviation of 3.1. Set up the null and alternative hypotheses, and use alpha = 0.05. Test the null hypothesis and give the p-value (4).
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