We intend to estimate the average driving time of a group of commuters. From a previous study, we believe that the average time is 55 minutes with a standard deviation of 13 minutes. We want our 90% confidence interval to have a margin of error of no more than plus or minus 1 minute. What is the smallest sample size that we should consider?

Please read the passage on Random Distribution for Arsenic of Chicken first and then answer the question carefully to get the correct answer.

If the sample size (n) and probability of success (p) are given, which equations are used to determine the mean and standard deviation?  Be specific.

Suppose that Dietitians recently recommended a 400 cal per meal and take her children of the age of the data set.  To see if both groups adhere to the guideline follow the steps to develop and test a statistical hypothesis.  Test to see if us groups means are different from 400 calories.  You have two data sets so you'll be completing the process twice.  Use 0.05 as a level of significance and make sure to report any important statistic with your results (e.g., mean of each group, standard deviation of each group, test stastistic (are you using t or z?), rejection region and p value).   Data: Children Participated Children Did Not Participate 435.16 414.61 338.99 503.46 488.73 425.22 590.28 288.77 582.59 184 635.21 299.73 249.86 350.65 441.66 394.94 572.43 261.55 357.78 295.28 396.79 139.69 298.38 462.78 282.99 179.59 368.51 301.75 388.59 436.58 256.32 371.39 408.82 469.02 424.94 378.09 477.96 287.31 428.74 448.55 432.52 332.64 428.27…

If this​ 3-year-old boy grows up to be a man with a height at the same​ percentile, what will his height​ be? Use a population mean of 70 inches and a population standard deviation of 3 inches

You may need to use the appropriate appendix table or technology to answer this question. The U.S. Energy Information Administration (US EIA) reported that the average price for a liter of regular gasoline is $0.78. The US EIA updates its estimates of average gas prices on a weekly basis. Assume the standard deviation is $0.06 for the price of a liter of regular gasoline and recommend the appropriate sample size for the US EIA to use if they wish to report each of the following margins of error at 95% confidence. (Round your answers up to the nearest whole number.) (a) The desired margin of error is $0.04. (b) The desired margin of error is $0.03. (c) The desired margin of error is $0.01.

What effect does increasing the sample size have on the population standard deviation? I know that it decreases, but why?

Suppose that you randomly survey death records for people born in 1900 in Louisiana and compared the life span of two different ethnicities. Of the 109 individuals sampled from ethnicity 1, the mean life span was 45.5 years with a standard deviation of 18.2 years. Of the 105 individuals sampled from ethnicity 2, the mean life span was 44.9 years with a standard deviation of 11.4 years. Conduct a hypothesis test with a 10% level of significance to see if the mean life spans in Louisiana were the same for the two ethnicities. Step 1: State the null and alternative hypotheses. Ho: µ1 – µ2 =v Ha:H1 – µ2 # v (So we will be performing a two-tailed ♥ test.)

Can you please help me with this problem Thank you in advance.

Ivanna recently switched her primary doctor to one specializing in caring for elderly patients. On her new doctor's website, it says that the mean systolic blood pressure among elderly females is 120 millimeters of mercury (mmHg). Ivanna believes the value is actually higher. She bases her belief on a recently reported study of 18 randomly selected, elderly females. The sample mean systolic blood pressure was 125 mmHg, and the sample standard deviation was 22 mmHg. Assume that the systolic blood pressures of elderly females are approximately normally distributed. Based on the study, at the 0.05 level of significance, can it be concluded that μ, the population mean systolic blood pressure among elderly females, is greater than 120 mmHg? Perform a one-tailed test. Then complete the parts below. Carry your intermediate computations to three or more decimal places. (If necessary, consult a list of formulas.) (a) State the null hypothesis Ho and the alternative hypothesis H₁. 0 Ho ! H₁ (b)…