A Telecom service provider claims that individual customers pay on average $400 per month.A random sample of 50 customers' bills during a given month is taken with a mean of $250 and standarddeviation of $15.(a) What to say with respect to the claim made by the service provider?(b) Report a 95% two-sided confidence interval for the mean paid per month.

Answered: A Telecom service provider claims that…

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 water usages in American showers are normally distributed, with an average shower using 20 gallons, and a standard deviation of 3.2 gallons. Estimate the percentage of showers that used (a) between 13.6 and 26.4 gallons. % (b) more than 26.4 gallons. % (c) less than 10.4 gallons. % (d) between 16.8 and 29.6 gallons. %
Insurance Company A claims that its customers pay less for car insurance, on average, than customers of its competitor, Company B. You wonder if this is true, so you decide to compare the average monthly costs of similar insurance policies from the two companies. For a random sample of 13 people who buy insurance from Company A, the mean cost is $150 per month with a standard deviation of $19. For 9 randomly selected customers of Company B, you find that they pay a mean of $157 per month with a standard deviation of $16. Assume that both populations are approximately normal and that the population variances are equal to test Company A's claim at the 0.05 level of significance. Let customers of Company A be Population 1 and let customers of Company B be Population 2. Step 1 of 3: State the null and alternative hypotheses for the test. Fill in the blank below. Ho: M₁ = μ₂ Ha:M₁ •H₂
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A national online business magazine reports that the average cost of a speeding ticket in Miami, including court fees, is $220. A local police department claims that this amount has increased. To test their claim, they collect data from a simple random sample of 16 drivers who have been fined for speeding in the last year. Assuming that the distribution of speeding ticket costs is normally distributed and the population standard deviation is $14, is there sufficient evidence to support the police department's claim at the 0.02 level of significance? Copy Data Speeding Ticket Costs in Miami $226 $215 $200 $248 $233 $242 $213 $247 $217 $221 $237 $217 $232 $211 $241 $212 Step 1 of 3: State the null and alternative hypotheses for the test. Fill in the blank below. Họ : 1 = 220 Hap 220

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