The following random samples are measurements of the heat-producing capacity (in millions of calories per ton) of coal from two mines: Mine 1: 8380, 8180, 8500, 7840, 7990 Mine 2: 7660, 7510, 7910, 8070, 7790 Use the 0.05 level of significance to test whether the difference between the means of these two samples is significant. Instructions: Assume 8 = 0, in addressing the problem obtain the value of the test statistic and its corresponding p – value up to four decimal places.

1.56 Longleaf pine trees. The Wade Tract in Thomas County, Georgia, is an old-growth forest of longleaf pine trees (Pinus palustris) that has survived in a relatively undisturbed state since before the settlement of the area by Europeans. A study collected data on 584 of these trees. One of the variables measured was the diameter at breast height (DBH). This is the diameter of the tree at 4.5 feet, and the units are centimeters (cm). Only trees with DBH greater than 1.5 cm were sampled. Here are the diameters of a random sample of 40 of these trees: PINES 27 10.5 13.3 26.0 18.3 52.2 9.2 26.1 17.6 40.5 31.8 47.2 11.4 2.7 69.3 44.4 16.9 35.7 5.4 44.2 2.2 4.3 7.8 38.1 2.2 11.4 51.5 4.9 39.7 32.6 51.8 43.6 2.3 44.6 31.5 40.3 22.3 43.3 37.5 29.1 27.9 (a) Find the five-number summary for these data. (b) Make a boxplot. (c) Make a histogram. (d) Write a short summary of the major features of this distribution. Do you prefer the boxplot or the histogram for these data?

The 5- number summary is 0.53, 0.74, 1.19, 1.355, and 1.49

One operation of a mill is to cut pieces of steel into parts that will later be used as the frame for front seats in an automobile. The steel is cut with a diamond saw and requires the resulting parts to be within 10.005 inch of the length specified by the automobile company. Data are collected from a sample of 50 steel parts and are shown in the following table. The measurement reported is the difference in inches between the actual length of the steel part, as measured by a laser measurement device, and the specified length of the steel part. For example, the first value, -0.003, represents a steel part that is 0.003 inch shorter than the specified length. Complete parts a through c Click the icon to view the data table. a. Construct a frequency distribution Difference in Length -0.005 but less than -0.003: -0.003but less than -0.001 -0.001but less than 0.001 0.001but less than 0.003 0.003but less than 0.005 Frequency Difference Between Actual and Specified Lengths 0.002 0 -0.003…

Thomas wants to compare the mean concentration of carbon monoxide (CO) on residential versus commercial streets, since these differ in terms of car traffic. In each of three neighborhoods of Montréal (named A, B, and C below), he randomly chooses four locations for each type of street, for a total of 24 observations (2 street types x 3 neighborhoods x 4 locations). At each location, he measures CO concentration in the air over a period of 10 hours (8:00 AM-6:00 PM), and obtains the following data (in ppm/h). Question: Test whether or not the difference between residential and commercial streets in mean atmospheric CO concentration is the same among the three neighborhoods, and whether or not CO concentration in the air is the same, on average, for the two types of streets. Note that Neighborhood is considered a random block factor in the ANOVA. Use significant level= 0.05.

Exhibit 10-11An insurance company selected samples of clients under 18 years of age and over 18 and recorded the number of accidents they had in the previous year. The results are shown below. Under Age 18 Over Age 18 n1 = 500 n2 = 600 Number of accidents = 180 Number of accidents = 150 We are interested in determining if the accident proportions differ between the two age groups.   Refer to Exhibit 10.11. The p-value is _____. Group of answer choices less than .001 more than .10 .0228 .3

A sample of blood pressure measurements is taken for a group of​ adults, and those values​ (mm Hg) are listed below. The values are matched so that 10 subjects each have a systolic and diastolic measurement. Find the coefficient of variation for each of the two​ samples;then compare the variation.   a. The coefficient of variation for the systolic measurements is ​(Type an integer or decimal rounded to one decimal place as​ needed.)   b. The coefficient of variation for the diastolic measurements is ​(Type an integer or decimal rounded to one decimal place as​ needed.)

Fill the chi square for Cross 1 and Cross 2 from the following data in the attached image: Cross 1: Phenotypes Ratio Observed Expected (O-E)2/E                                         Totals       X2 =  Cross 2: Phenotypes Ratio Observed Expected (O-E)2/E                                         Totals       X2 =

All data entries are listed in Excel photo.

The "spring-like effect" in a golf club could be determined by measuring the coefficient of restitution (the ratio of the outbound velocity to the inbound velocity of a golf ball fired at the clubhead). Twelve randomly selected drivers produced by two clubmakers are tested and the coefficient of restitution measured. The data follow: Club 1: 0.8406, 0.8104, 0.8234, 0.8198, 0.8235, 0.8562, 0.8123, 0.7976, 0.8184, 0.8265, 0.7773, 0.7871  Club 2: 0.8305, 0.7905, 0.8352, 0.8380, 0.8145, 0.8465, 0.8244, 0.8014, 0.8309, 0.8405, 0.8256, 0.8476 Test the hypothesis that both brands of ball have equal mean overall distance. Use α = 0.05 and assume equal variances. Question: Reject H0 if t0 < ___ or if t0 > ___.