An article gave the following summary information for fracture strengths (mpa) of n = 169 ceramic bars fired in a particular kiln: x = 34.30, s = 3.92. calculate a (two-sided) confidence interval for true average fracture strength using a confidence level of 95%. (round your answers to two decimal places.) ) mpa does it appear that true average fracture strength has been precisely estimated? yes, this is a very narrow interval. no, this is a very wide interval. (b) suppose the investigators had believed a priori that the population standard deviation was about 4 mpa. based on this supposition, how large a sample would have been required to estimate to within 0.5 mpa with 95% confidence? ceramic bars you may need to use the appropriate table in the appendix of tables to answer this question.

What is the standard deviation of the following data set rounded to the nearest tenth? 3, 17, 18, 15, 12, 21, 9

Find the area and perimeter of each composite figure. use 3.14 for π. round your answer to the nearest tenth. a square and a right triangle share a common side. image long description a 3-meter by 0.5-meter rectangle has triangles attached like wings to the 3-meter sides. the other two sides of both triangles measure 2.5 meters. the height of each triangle is 2 meters. a 6-inch by 4-inch rectangle has 2 half-circles attached like wings to the 6-inch sides. the radius of each half-circle is 3 inches. find the surface area and volume of each figure. use 3.14 for π. round your answer to the nearest tenth. a right circular cylinder has a base radius of 6 yards and a height of 20 yards. a rectangular prism has a base that is 9 centimeters long and 7 centimeters wide. the height is 2 centimeters. a rectangular prism has a base that measures 11 millimeters by 11 millimeters. the height is 11 millimeters.

10 ! a train starts from grand city and travels toward belleville 388 miles away. at the same time, a train starts from belleville and runs at the rate of 47 miles per hour toward grand city. they pass each other 4 hours later. find the rate of the train from grand city.