Cigarette Smoking A researcher found that a cigarette smoker smokes on average 30 cigarettes a day. She feels that this average is too low. She selected a random sample of 11 smokers and found that the mean number of cigarettes they smoked per day was 31. The sample standard deviation was 2.6. At =α0.10, is there enough evidence to support her claim? Assume that the population is approximately normally distributed. Use the critical value method and tables. (a)State the hypotheses and identify the claim.     (b)Find the critical value.     (c)Compute the test value.     (d)Make the decision.     (e)Summarize the results.

The concentration of benzene was measured in units of milligrams per liter for a simple random sample of five specimens of untreated wastewater produced at a gas field. The sample mean was 4.6 with a sample standard deviation of 2.7. Seven specimens of treated wastewater had an average benzene concentration of 7.9 with a standard deviation of 2.3. It is reasonable to assume that both samples come from populations that are approximately normal. Can you conclude that the mean benzene concentration differs between treated water and untreated water? Let h1  denote the mean benzene concentration for untreated water and h2 denote the mean benzene concentration for treated water. Use the a=0.05 level the p-value method with the TI-84 Plus calculator.     please show p value!

A science teacher claims that the mean scores on a science assessment test for fourth grade boys and girls are equal. The mean score for 18 randomly selected boys is 153 with a standard deviation of 23 and the mean score for 20 randomly selected girls is 149 with a standard deviation of 30. At α=0.01, can you reject the teacher’s claim? Assume the populations are normally distributed and the variance are not equal. Include a filled out standardized test statistic formula. You may not use the following df formula for this problem

Suppose that for the past several decades, daily precipitation in Seattle, Washington has had a mean of 2.4 mm and a standard deviation of 11.4 mm. Researchers suspect that in recent years, the mean amount of daily precipitation has changed, so they plan to obtain data for a random sample of 195 days over the past five years and use this data to conduct a one-sample ?z‑test of ?0:?=2.4H0:μ=2.4 mm against ?1:?≠2.4H1:μ≠2.4 mm, where ?μ is the mean daily precipitation for the last five years. Although they realize that rainfall does not follow a normal distribution, they feel safe using a ?z‑test because the sample size is large. The researchers want to know what the power of this test is to reject the null hypothesis at significance level ?=0.05α=0.05 if the actual mean daily precipitation is 2.6 mm or more. Computing power by hand requires two steps. The first step is to use a significance level of 0.05 to determine the values of the sample mean for which they will reject their null…

A local bottler in Hawaii wishes to ensure that an average of 10 ounces of passion fruit juice is used to fill each bottle. In order to analyze the accuracy of the bottling process, he takes a random sample of 39 bottles. The mean weight of the passion fruit juice in the sample is 9.54 ounces. Assume that the population standard deviation is 1.25 ounce. (You may find it useful to reference the appropriate table: z table or t table) Select the null and the alternative hypotheses to test if the bottling process is inaccurate.   multiple choice 1 H0: μ = 10; HA: μ ≠ 10 H0: μ ≤ 10; HA: μ > 10 H0: μ ≥ 10; HA: μ < 10 b-1. Calculate the value of the test statistic. (Negative value should be indicated by a minus sign. Round intermediate calculations to at least 4 decimal places and final answer to 2 decimal places.)   b-2. Find the p-value. 0.05 p-value < 0.10 p-value 0.10 p-value < 0.01 0.01 p-value < 0.025 0.025 p-value < 0.05 c-1. What is the conclusion at α = 0.01?…

In a sample of 14 randomly selected high school seniors, the mean score on a standardized test was 1197 and the standard deviation was 166.9. Further research suggests that the population mean score on this test for high school seniors is 1018. Does the t-value for the original sample fall between -to.95 and to.95? Assume that the population of test scores for high school seniors is normally distributed. fall between -to.95 and to.95 because to.95 = The t-value of t= (Round to two decimal places as needed.) C

A company that makes cola drinks states that the mean caffeine content per​ 12-ounce bottle of cola is 45 milligrams. You want to test this claim. During your​ tests, you find that a random sample of thirty​ 12-ounce bottles of cola has a mean caffeine content of 46.7 milligrams. Assume the population is normally distributed and the population standard deviation is 7.7 milligrams. At α=0.05​, can you reject the​ company's claim? Complete parts​ (a) through​ (f). ​(a) Identify H0 and Ha. ​(b) Find the critical​ value(s). Select the correct choice below and fill in the answer box within your choice. c) Identify the rejection​ region(s). Choose the correct answer below. d) Find the standardized test statistic. e) Decide whether to reject or fail to reject the null hypothesis. f) Interpret the decision in the context of the original claim.

In a random sample of 10 cell​ phones, the mean full retail price was ​$507.20 and the standard deviation was ​$194.00. Further research suggests that the population mean is ​$426.53. Does the​ t-value for the original sample fall between −t0.95 and t0.95​? Assume that the population of full retail prices for cell phones is normally distributed.   The​ t-value of t=enter your response here ▼     fall between −t0.95 and t0.95 because t0.95=enter your response here. ​(Round to two decimal places as​ needed.)

A company that makes cola drinks states that the mean caffeine content per​ 12-ounce bottle of cola is 35 milligrams. You want to test this claim. During your​ tests, you find that a random sample of thirty​ 12-ounce bottles of cola has a mean caffeine content of 33.4 milligrams. Assume the population is normally distributed and the population standard deviation is 7.9 milligrams. At α=0.05​, can you reject the company's claim?   -Identify Ho and Ha. -Find the critical value and sketch the region -Calculate the test statistic -Do you reject Ho or fail to reject Ha

A company that makes cola drinks states that the mean caffeine content per​ 12-ounce bottle of cola is 35 milligrams. You want to test this claim. During your​ tests, you find that a random sample of thirty​ 12-ounce bottles of cola has a mean caffeine content of 35.4 milligrams. Assume the population is normally distributed and the population standard deviation is 7.9 milligrams. At α=0.05​, can you reject the​ company's claim? Complete parts​ (a) through​ (e).   Part 1​(a) Identify H0 and Ha.   Choose the correct answer below. A.) H0​:μ≥35.4       Ha​:μ<35.4   B.) H0​:μ≠35       Ha​:μ=35   C.) H0​:μ=35       Ha​:μ≠35   D.) H0​: μ≥35       Ha​: μ<35   E.) H0​: μ≠35.4      Ha​:μ=35.4   F.) H0​: μ=35.4     Ha​:μ≠ 35.4   (b) Find the critical​ value(s). Select the correct choice below and fill in the answer box within your choice.   ​(c) Find the standardized test statistic.       z=   ​(d) Decide whether to reject or fail to reject…