An airline company would like to know if the average number of passengers on a flight in November is less than the average number of passengers on a flight in December. The results of random sampling are printed below. Test the appropriate hypotheses using α = 0.01.  A random sample of 200 passengers is taken in both months. The null and alternate hypothesis used: H0: mu1-mu2=0 vs. Ha: mu1-mu2<0 The test statistic is: -4.62 What is the correct conclusion?   A. There is not enough information given   B. Accept the null hypothesis   C. Reject the null hypothesis   D. Fail to reject the null hypothesis

Words were displayed on a computer screen with background colors of red and blue. Results from scores on a test of word recall are given below. Use a 0.05 significance level to test the claim that the samples are from populations with the same standard deviation. Assume that both samples are independent simple random samples from populations having normal distributions. Does the background color appear to have an effect on the variation of word recall scores? Red Background Blue Background What are the null and alternative hypotheses? OA H₂:0²=0²₂2 H₁: 0²1 20²2 n X S 34 15.35 5.94 37 12.49 5.43 *C. H₂:0² = 0²/ c. H₁:0² #0²/2 Identify the test statistic. F = (Round to two decimal places as needed.) *** B. H₂:0² = 0² H₁:0² <0² OD. H₂:0² #0²/2 H₁:0² = 0²

In a pilot study to compare pre-intervention and post-intervention outcomes, five pairs are used. The differences (POST - PRE) are calculated to be0,−1,3,0, and - 2 . Which of following statement is not correct? The sample mean of the differences is 0 . An estimate for the standard error of the sample mean difference is 1.871 . Thet-statistic for testing the null hypothesis HO: Delta=0(i.e., the true mean difference is zero) is 0 . None of the above.

A traffic coordinator for a community wishes to determine whether or not there is any difference in the average age of female and male drivers involved in rear-end accidents. The hypothesis test is: Ho: 41 = 42 (no difference in mean age) 10 H1: (mean age is different) A random sample of males and females involved in rear-end accidents results in the following Minitab summary: N MEAN MEDIAN TRMEAN STDEV SE MEAN FEMALES 33 23.91 20.00 23.38 9.77 1.70 MALES 38 28.87 28.50 28.44 9.67 1.57 а). What is the value of the test statistic? Appropriate test: Test statistic = b). What is the decision rule at the 0.025 level of significance? с). What is the conclusion?

A diet doctor claims that the average North American is more than 20 poundsoverweight. To test this claim, a random sample of 20 North Americans was weighed,and the difference between their actual and ideal weights was calculated. The statisticscalculated from the sample were ?̅= 21.2 and ? = 6.7. Do these data allow us to infer atthe 6% significance level that the doctor’s claim is true? Provide your analysis andconclusion.

What is tcrit for a one sample, one tailed t-test, with n=13 and α=0.05?

A t-test is used to test hypotheses for the population mean . A random sample of 25 is selected for the analysis. How many degrees of freedom would be used for the test?

The sales manager of a food company wants to determine if the weekly sales of 16 ounce packages of frozen broccoli has increased since last year. The mean weekly number of sales per store was 2,400 packages last year. The sales manager set the following hypotheses to test Hol=2400 H₁:H>2400 Available sales data are from 400 stores. Assume that this data set is a random sample. The sample mean is 2,430 and the sample standard deviation is 800. For the significance level of 5%, find the critical value. a) 2478.4 b) 2430 Oc) 2321.6 d) 2334.4 e) 2465.6

Listed in the data table are IQ scores for a random sample of subjects with medium lead levels in their blood.Also listed are Satistics from a study done of IQ scores for a random sample of subjects with high lead levels. Assume that the two samples are independent simple random samples selected from normally distibuted populations. Do not assume that the population standard deviations are equal. What are the null and alternative hypothesis? Assume population 1 consist subjects with medium lead levels and population 2 consist of subjects with high lead levels. The test satistic is?The P value is?State a conclusion for the testConstruct a confidence interval suitable for the claim that the mean IQ scores for subjects with a medium lead level is higher than the mean for subjects with high lead levels.