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Cooling method for gas turbines. During periods of high electricity demand, especially during the hot summer months, the power output from a gas turbine engine can drop dramatically. One way to counter this drop in power is by cooling the inlet air to the gas turbine. An increasingly popular cooling method uses high-pressure inlet fogging. The performance of a sample of 67 gas turbines augmented with high-pressure inlet fogging was investigated in the Journal of Engineering for Gas Turbines and Power (January 2005). One measure of performance is heat rate (kilojoules per kilowatt per hour). Heat rates for the 67 gas turbines are listed in the table below. Suppose that standard gas turbines have heat rates with a standard deviation of 1,500 kJ/kWh. Is there sufficient evidence to indicate that the heat rates of the augmented gas turbine engine are more variable than the heat rates of the standard gas turbine engine? Test using α = .05.
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Statistics for Business and Economics (13th Edition)
- What does the y -intercept on the graph of a logistic equation correspond to for a population modeled by that equation?arrow_forwardInorganic phosphorous is a naturally occurring element in all plants and animals, with concentrations increasing progressively up the food chain (fruit < vegetables < cereals < nuts < corpse). Geochemical surveys take soil samples to determine phosphorous content (in ppm, parts per million). A high phosphorous content may or may not indicate an ancient burial site, food storage site, or even a garbage dump. Independent random samples from two regions gave the following phosphorous measurements (in ppm). Assume the distribution of phosphorous is mound-shaped and symmetric for these two regions Region I: x1; n1 = 15 855 1550 1230 875 1080 2330 1850 1860 2340 1080 910 1130 1450 1260 1010 Region II: x2; n2 = 14 540 810 790 1230 1770 960 1650 860 890 640 1180 1160 1050 1020 (a) Use a calculator with mean and standard deviation keys to verify that x1, s1, x2, and s2. (Round your answers to one decimal place.) x1 = ppm s1 = ppm x2 = ppm s2 = ppm…arrow_forwardInorganic phosphorous is a naturally occurring element in all plants and animals, with concentrations increasing progressively up the food chain (fruit < vegetables < cereals < nuts < corpse). Geochemical surveys take soil samples to determine phosphorous content (in ppm, parts per million). A high phosphorous content may or may not indicate an ancient burial site, food storage site, or even a garbage dump. Independent random samples from two regions gave the following phosphorous measurements (in ppm). Assume the distribution of phosphorous is mound-shaped and symmetric for these two regions. Region 1: x1;n1=15 857 1,551 1,230 875 1,080 2,330 1,850 1,860 2,340 1,080 910 1,130 1,450 1,260 1,010 region 11: x2;n2-14 538 812 790 1,230 1,770 960 1,650 860 890 640 1,180 1,160 1,050 1,020 (a)Use a calculator with mean and standard deviation keys to verify that x1, s1, x2, and s2. (Round your answers to four decimal places.) x1= ppm s1= ppm x2= ppm s2= ppm…arrow_forward
- Inorganic phosphorous is a naturally occurring element in all plants and animals, with concentrations increasing progressively up the food chain (fruit < vegetables < cereals < nuts < corpse). Geochemical surveys take soil samples to determine phosphorous content (in ppm, parts per million). A high phosphorous content may or may not indicate an ancient burial site, food storage site, or even a garbage dump. Independent random samples from two regions gave the following phosphorous measurements (in ppm). Assume the distribution of phosphorous is mound-shaped and symmetric for these two regions. Region I: x1; n1 = 15 857 1,551 1,230 875 1,080 2,330 1,850 1,860 2,340 1,080 910 1,130 1,450 1,260 1,010 Region II: x2; n2 = 14 538 808 790 1,230 1,770 960 1,650 860 890 640 1,180 1,160 1,050 1,020 (a) Use a calculator with mean and standard deviation keys to verify that x1, s1, x2, and s2. (Round your answers to four decimal places.) x1= 1387.5333 ppm s1=…arrow_forwardInorganic phosphorous is a naturally occurring element in all plants and animals, with concentrations increasing progressively up the food chain (fruit < vegetables < cereals < nuts < corpse). Geochemical surveys take soil samples to determine phosphorous content (in ppm, parts per million). A high phosphorous content may or may not indicate an ancient burial site, food storage site, or even a garbage dump. Independent random samples from two regions gave the following phosphorous measurements (in ppm). Assume the distribution of phosphorous is mound-shaped and symmetric for these two regions. Region I: x,; n, = 15 853 1,551 1,230 1,080 2,330 1,850 1,860 875 2,340 1,080 910 1,130 1,450 1,260 1,010 Region II: x,; n, = 14 540 1,230| 1,770 808 790 960 1,650 860 890 640 1,180 1,160 | 1,050 1,020 In USE SALT (a) Use a calculator with mean and standard deviation keys to verify that x,, S,, x2, and s,. (Round your answers to four decimal places.) x, = X1 ppm S1 ppm X2 ppm S2 , = ppm (b) Let…arrow_forwardInorganic phosphorous is a naturally occurring element in all plants and animals, with concentrations increasing progressively up the food chain (fruit < vegetables < cereals < nuts < corpse). Geochemical surveys take soil samples to determine phosphorous content (in ppm, parts per million). A high phosphorous content may or may not indicate an ancient burial site, food storage site, or even a garbage dump. Independent random samples from two regions gave the following phosphorous measurements (in ppm). Assume the distribution of phosphorous is mound-shaped and symmetric for these two regions. REGION I:X1;N1=15 857 1,551 1,230 875 1,080 2,330 1,850 1,860 2,340 1,080 910 1,130 1,450 1,260 1,010 REGION II:X2;N2=14 538 812 790 1,230 1,770 960 1,650 860 890 640 1,180 1,160 1,050 1,020 (a) Use a calculator with mean and standard deviation keys to verify that x1, s1, x2, and s2. (Round your answers to four decimal places.) x1= ppm s1= ppm x2= ppm s2= ppm…arrow_forward
- Inorganic phosphorous is a naturally occurring element in all plants and animals, with concentrations increasing progressively up the food chain (fruit < vegetables < cereals < nuts < corpse). Geochemical surveys take soil samples to determine phosphorous content (in ppm, parts per million). A high phosphorous content may or may not indicate an ancient burial site, food storage site, or even a garbage dump. Independent random samples from two regions gave the following phosphorous measurements (in ppm). Assume the distribution of phosphorous is mound-shaped and symmetric for these two regions Region I: x1; n1 = 15 855 1550 1230 875 1080 2330 1850 1860 2340 1080 910 1130 1450 1260 1010 Region II: x2; n2 = 14 540 810 790 1230 1770 960 1650 860 890 640 1180 1160 1050 1020 (a) Use a calculator with mean and standard deviation keys to verify that x1, s1, x2, and s2. (Round your answers to one decimal place.) x1 = ppm s1 = ppm x2 = ppm s2 = ppm…arrow_forwardInorganic phosphorous is a naturally occurring element in all plants and animals, with concentrations increasing progressively up the food chain (fruit < vegetables < cereals < nuts < corpse). Geochemical surveys take soil samples to determine phosphorous content (in ppm, parts per million). A high phosphorous content may or may not indicate an ancient burial site, food storage site, or even a garbage dump. Independent random samples from two regions gave the following phosphorous measurements (in ppm). Assume the distribution of phosphorous is mound-shaped and symmetric for these two regions. Region I: x,; n, = 15 857 1,553 1,230 875 1,080 2,330 1,850 1,860 2,340 1,080 910 1,130 1,450 1,260 1,010 Region II: x2; n2 = 14 538 810 790 1,230 1,770 960 1,650 860 890 640 1,180 1,160 1,050 1,020 n USE SALT (a) Use a calculator with mean and standard deviation keys to verify that x,, s,, X2, and s,. (Round your answers to four decimal places.) X, = ppm S, = ppm X2 ppm S2 ppm %3D (b) Let u, be…arrow_forwardInorganic phosphorous is a naturally occurring element in all plants and animals, with concentrations increasing progressively up the food chain (fruit < vegetables < cereals < nuts < corpse). Geochemical surveys take soil samples to determine phosphorous content (in ppm, parts per million). A high phosphorous content may or may not indicate an ancient burial site, food storage site, or even a garbage dump. Independent random samples from two regions gave the following phosphorous measurements (in ppm). Assume the distribution of phosphorous is mound-shaped and symmetric for these two regions. Region I: x1; n1 = 15 853 1,549 1,230 875 1,080 2,330 1,850 1,860 2,340 1,080 910 1,130 1,450 1,260 1,010 Region II: x2; n2 = 14 538 808 790 1,230 1,770 960 1,650 860 890 640 1,180 1,160 1,050 1,020 (a) Use a calculator with mean and standard deviation keys to verify that x1, s1, x2, and s2. (Round your answers to four decimal places.) x1= ppm s1= ppm x2= ppm s2=…arrow_forward
- Challenger Disaster: a,b and carrow_forwardInorganic phosphorous is a naturally occurring element in all plants and animals, with concentrations increasing progressively up the food chain (fruit < vegetables < cereaise nuts < corpse). Geochemical surveys take soil samples to determine phosphorous content (in ppm, parts per million). A high phosphorous content may or may not indicate an ancient burial site, food storage site, or even a garbage dump. Independent random samples from two regions gave the following phosphorous measurements (in ppm). Assume the distribution of phosphorous is mound-shaped and symmetric for these two regions. Region It x n, 15 857 1,551 1,230 875 1,080 2,330 1,850 1,860 2,340 1,080 910 1,130 1,450 1,260 1,010 Region III xi n 14 542 B06 1,230 1,770 790 960 1,650 860 890 640 1,180 1,160 1,050 1,020 A USE SALT (a) Use a caiculator with mean and standard deviation keys to verify that a and s (Round your answers to four decimal places.) ppm ppm ppm ppm (b) Let , be the population mean for x, and let be the…arrow_forwardAn article in Lubrication Engineering (December 1990) described the results of an experiment designed to investigate the effects of carbon material properties on the progression of blisters on carbon face seals. The carbon face seals are used extensively in equipment such as air turbine starters. Four different carbon materials were tested, and the surface roughness was measured. The data are as follows: Carbon Material Type Surface Roughness EC10 0.5 0.55 0.55 0.36 EC10A 0.31 0.07 0.25 0.18 0.56 0.2 EC4 0.2 0.28 0.12 EC1 0.1 0.16 Does carbon material type have an effect on mean surface roughness? Use α = 0.05.arrow_forward
- Linear Algebra: A Modern IntroductionAlgebraISBN:9781285463247Author:David PoolePublisher:Cengage LearningGlencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill