An economist is studying salaries for high technology companies and wants to test the claim that the average salary for high tech employees is less than $70,000. The economist selects a sample of 35 random employees from various high tech companies and records their salaries.  Based on past studies, the economist determines that the population standard deviation is $8,500. The economist conducts a one-mean hypothesis test at the 5% significance level to test the claim that the average salary for high tech employees is less than $70,000. Which is the correct setup for the null and alternative hypothesis for this example? Select the correct answer below: H0:μ=70,000; Ha:μ<70,000, which is a left-tailed test. H0:μ=70,000; Ha:μ>70,000, which is a right-tailed test H0:μ<70,000; Ha:μ=70,000, which is a left-tailed test. H0:μ>70,000; Ha:μ=70,000, which is a left-tailed test.

I would like to test the hypothesis that the average round trip airfare between Phoenix and San Diego is higher for a flight originating in Phoenix when compared to a flight originating in San Diego. The following data summarizes the sample statistics for round trip flights originating in both cities. Originating City Phoenix San Diego Sample mean $240 $160 Sample size 18 18 Sample standard deviation $70 $40 If Population 1 is defined as flights originating in Phoenix and Population 2 is defined as flights originating in San Diego, the 90% confidence interval for the difference in population means is O ($50.20, $109.80) O ($42.80, $117.20) ($47.80, $112.20) O ($51.80, $108.20)

A credit score is used by credit agencies​ (such as mortgage companies and​ banks) to assess the creditworthiness of individuals. Values range from 300 to 850 with a credit score over 700 considered to be a quality credit risk. According to a​ survey, the mean credit score is 705.6. A credit analyst wondered whether​ high-income individuals​ (incomes in excess of​ $100,000 per​ year) had higher credit scores. He obtained a random sample of 34 high-income individuals and found the sample mean credit score to be 724.4 with a standard deviation of 84.4. Conduct the appropriate test to determine if​ high-income individuals have higher credit scores at the α=0.05 level of significance. 1) Find: P-value  2) Make a conclusion regarding the hypothesis.

Two researchers conducted a study in which two groups of students were asked to answer 42 trivia questions from a board game. The students in group 1 were asked to spend 5 minutes thinking about what it would mean to be a​ professor, while the students in group 2 were asked to think about soccer hooligans. These pretest thoughts are a form of priming. The 200 students in group 1 had a mean score of 23.5 with a standard deviation of 4.3​, while the 200 students in group 2 had a mean score of 17.7 with a standard deviation of 4.1. Complete parts ​(a) and ​(b) below. (a) Determine the 95​% confidence interval for the difference in​ scores, μ1−μ2. Interpret the interval.   The lower bound is __. The upper bound is ___ ​(Round to three decimal places as​ needed.)   B Interpret the interval. Choose the correct answer below.     A. The researchers are 95​% confident that the difference of the means is in the interval.   B. There is a 95​% probability that the difference of the means is…