The following null hypothesis is given. Η μ S 230 A sample of 50 observations is selected from a normal population. The sample mean is 250, and the population standard deviation is 45. Assume it follows Z-distribution and test at a = 0.05.

T3.6

A random sample of  n1 = 49  measurements from a population with population standard deviation  ?1 = 3  had a sample mean of  x1 = 9.  An independent random sample of  n2 = 64  measurements from a second population with population standard deviation  ?2 = 4  had a sample mean of  x2 = 11.  Test the claim that the population means are different. Use level of significance 0.01.

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Medical Operations The director of a medical hospital feels that her surgeons perform fewer operations per year than the national average of 211. She selected a random sample of 15 surgeons and found that the mean number of operations they performed was 210.6. The standard deviation of the sample was 3.8. Is there enough evidence to support the director's feelings at =α0.10? Assume that the population is approximately normally distributed. Use the critical value method and tables.a. State the hypotheses and identify the claim H0=    (claim or not claim)  H1=    (claim or not claim) This hypothesis test is a (one tailed or two tailed) test Critical value(s)= t= (Reject or do not reject) the null hypothesis  is there enough evidence to support the claim?

Suppos are interested in studying a population to estimate its mean. The population is normal and has a standard deviation of G=23. We have taken a random sample of size 11=95 from the population. This is Sample 1 in the table below. (In the table, Sample 1 is written "S1", Sample 2 is written "S2", etc.) As shown in the table, the sample mean of Sample 1 is = 142.0. Also shown are the lower and upper limits of the 80% confidence interval for the population mean using this sample, as well as the lower and upper limits of the 95% confidence interval. Suppose that the true mean of the population is = 140, which is shown on the displays for the confidence intervals. Press the "Generate Samples" button to simulate taking 19 more random samples of size 11 = 95 from this same population. (The 80% and 95% confidence intervals for all of the samples are shown in the table and graphed.) Then complete parts (a) through (c) below the table. 80% 80% 95% 95% lower upper lower upper limit limit…

A sample is selected from a population with A = 150. After a treatment is administered to the individuals, the sample mean is found to be = 140 and the standard deviation is S= 9. If the sample has n = 18 scores, determine whether the sample is sufficient to conclude that the treatment has significant effect. Use a two tail test with a = 0.02. (Assume the population is normally distributed)

A nutritionist claims that the mean tuna consumption by a person is 3.8 pounds per year. A sample of 70 people shows that the mean tuna consumption by a person is 3.5 pounds per year. Assume the population standard deviation is 1.04 pounds. At α=0.09​, can you reject the​ claim?     ​(a) Identify the null hypothesis and alternative hypothesis.     A. H0​: μ=3.8 Ha​: μ≠3.8   B. H0​: μ≠3.5 Ha​: μ=3.5   C. H0​: μ>3.5 Ha​: μ≤3.5   D. H0​: μ>3.8 Ha​: μ≤3.8   E. H0​: μ≤3.5 Ha​: μ>3.5   F. H0​: μ≤3.8 Ha​:μ>3.8   b) Identify the standardized test statistic. z= ​(Round to two decimal places as​ needed.)   (c) Find the​ P-value.   (d) Decide whether to reject or fail to reject the null hypothesis.     A. Reject H0. There is not sufficient evidence to reject the claim that mean tuna consumption is equal to 3.8pounds.   B. Reject H0. There is sufficient evidence to reject the claim that mean tuna consumption is equal to…

Find the p-value for the hypothesis test. A random sample of size 54 is taken. The sample has a mean of 375 and a standard deviation of 83. H0: µ = 400 Ha: µ< 400 The p-value for the hypothesis test is . rounded to 4 decimal places

A population has parameters μ=121.5 and σ=38.3. You intend to draw a random sample of size n=142.What is the mean of the distribution of sample means? μ¯x= What is the standard deviation of the distribution of sample means? (Report answer accurate to 2 decimal places.) σ¯x=