hey believe that one of the suppliers has a different variance than the other upplier and would like to perform a hypothesis test to support their claim. Both distributions are normal, and the populations are independent. use a = 0.01 "ο: στ2 = σ2 Ho:01 Supplier 1: standard deviation = 3.54, Sample size = 24 Supplier 2: standard deviation = 8, Sample size = 29. he test statistic (rounded to 4 decimal places) is = he p-value (rounded to 4 decimal places) is = O Reject the null hypothesis - there is enough evidence is support a meaningful difference in the variance of the suppliers. O Fail to reject the null hypothesis - there is not enough evidence to support a meaningful difference in the variance of the suppliers.

Previous research has shown that the mean number of ballpoint pens Americans use per year is 4.3 with a standard deviation of 1.17. You believe that amount is too high since computers are used so often this day and age. You randomly select 20 people and find the average to be 3.8 ballpoint pens per year. Assuming normality, is there evidence to show that the mean has decreased? What is the decision for this hypothesis test? Previous research has shown that the mean number of ballpoint pens Americans use per year is 4.3 with a standard deviation of 1.17. You believe that amount is too high since computers are used so often this day and age. You randomly select 20 people and find the average to be 3.8 ballpoint pens per year. Assuming normality, is there evidence to show that the mean has decreased? What is the decision for this hypothesis test?  Reject the null because the test statistic is in the critical region and the p-value is less than alpha.  Reject the null because the test…

Some college graduates employed full-time work more than 40 hours per week, and some work fewer than 40 hours per week. We suspect that the mean number of hours worked per week by college graduates, u, is different from 40 hours and wish to do a statistical test. We select a random sample of college graduates employed full-time and find that the mean of the sample is 44 hours and that the standard deviation is 4 hours. Based on this information, answer the questions below.

The mean number of English courses taken in a two-year time period by male and female college students is believed to be about the same. An experiment is conducted and data are collected from 24 males and 26 females. The males took an average of 4.2 English courses with a standard deviation of 1.1. The females took an average of 3.9 English courses with a standard deviation of 0.7. Conduct a hypothesis test at the 4% level of significance to determine whether the means are statistically the same. Step 1: State the null and alternative hypotheses. Ho: H1 = V H.: H1 – µ2 # v test.) (So we will be performing a two-tailed

Given that the researcher wants to be sure the mean difference in the change in hemoglobin levels has a margin of error no more than 0.2 g/dL and the difference in the stand deviation between the mean hemoglobin levels for the two forms of iron supplements used to treat anemia is 1.2 g/dL, what is the desired number of recruits for the study, assuming the individuals will participate in a crossover trial, if the study’s attrition rate is expected to be .25? Group of answer choices n = 139 n = 554 n = 185 n = 55,320

The mean annual income of certified welders is normally distributed with a mean of $50,000 and a population standard deviation of $8,000. The ship building association wishes to find out whether their welders earn more or less than $50,000 annually. The data collected from 36 certified welders indicate that the sample mean annual income is $47,500. If the level of significance is 0.10.What are the null and alternative hypothesis to test that the mean is not $50,000?     H0: µ ≤ $50,000; Ha: µ > $50,000     H0: µ  $47,500; Ha: µ ≠ $47,500     H0: µ  $50,000; Ha: µ ≠ $50,000     H0: µ ≥ $50,000; Ha: µ < $50,000

Research has shown that, for baseball players, good hip range of motion results in improved performance and decreased body stress. A research article reported on a study of independent samples of 40 professional pitchers and 40 professional position players. For the pitchers, the sample mean hip range of motion was 75.5 degrees and the sample standard deviation was 5.8 degrees, whereas the sample mean and sample standard deviation for position players were 79.1 degrees and 7.1 degrees, respectively. Assuming that the two samples are representative of professional baseball pitchers and position players, test hypotheses appropriate for determining if there is convincing evidence that the mean range of motion for pitchers is less than the mean for position players. (Use  ? = 0.05.  Use ?1 for pitchers and ?2 for position players.) State the appropriate null and alternative hypotheses.   Find the test statistic and P-value. (Use SALT. Round your test statistic to one decimal place and…

The average American consumes 86 liters of alcohol per year. Does the average college student consume more alcohol per year? A researcher surveyed 11 randomly selected college students and found that they averaged 95.8 liters of alcohol consumed per year with a standard deviation of 20 liters. What can be concluded at the the a = 0.05 level of significance? a. For this study, we should use t-test for a population mean O b. The null and alternative hypotheses would be: Ho: μ = H₁: μ > O 86 O 86 c. The test statistic (t) = d. The p-value = e. The p-value is ? a f. Based on this, we should Select an answer the null hypothesis. g. Thus, the final conclusion is that ... 1.625 (please show your answer to 3 decimal places.) (Please show your answer to 4 decimal places.) O The data suggest the population mean is not significantly more than 86 at a = 0.05, so there is statistically insignificant evidence to conclude that the population mean amount of alcohol consumed by college students is…

When 40 people used the Weight Watchers dies for one year, their mean weight loss was 3.0 lb and the standard deviation was 4.9 lb. Use a 0.01 significance level to test the claim that the mean weight loss is greater than 0. (Show the solution) A. The null hypothesis is                i. The mean weight loss is equal to 0. ii. The mean weight loss is not equal to 0. iii. The mean weight loss is greater than 0. iv. The mean weight loss is less than 0.   B. The computed t-test statistic is    i. 4.468 ii. 4.977 iii. 3.872 iv. 3.391   C. The critical/tabular t-test statistic is  i. 2.426 ii. 1.684 iii. 1.685 iv. 2.423   D. Decision rule:    i. Do not reject the null hypothesis. ii. Reject the null hypothesis.            E. The final conclusion is              i. The mean weight loss is not equal to 0 therefore Weight Watchers is effective. ii. The mean weight loss is less than 0 therefore Weight Watchers is not effective. iii. The mean weight loss is equal to 0 therefore Weight Watchers…

An experiment was performed to see if the color of paper an exam is printed on could affect scores on the exam. Doyle took a standardized exam on blue paper, usually it is taken on white, and scored 85. The national average on this exam is 70 with stardard deviation of 5. Use the z-scote method to determine if we can reject or fail to reject the null hypothesis based on the Doyle's data and national average.show work & justify your answer.