Question

Question 2 (1 point) An automobile manufacturer wishes to test that claim that synthetic motor oil can improve gas mileage (in miles per gallon, or mpg). The table below shows the gas mileages, in mpg, of six cars that used synthetic motor oil. The table also shows the gas mileages in mpg of six cars that were using conventional motor oil (the controls). Synthetic Control: 26 25 25 26 27 25 Can you conclude that the mean gas mileage for cars using synthetic motor oil is more than the mean for the controls? Use the a = 0.05 level of significance. Previous Page Next Page Page 2 of 4

Answer 1

lutions : woull Hypothesis (Ho)! There is no significance difference mean gas mileage for ears using synthetic motor and mean for the controls. Hool, = 42 Wternative Hypothesis (H): There is significant difference between mean gas mileage for cars using synthetic motor and mean for the controls Hp M, M2. (Right tailed Alternative) tot l (X; - x)² = (y-7) 2 (one 26 0,6889 26 011156 010289. 25 0.4356 125 3. 3489 noi 1 25 1 0.4356 , w ant 127 0.0289 26 0.1156 28 1.3689 27 10 7956 anom 28 1.3689 25 0.4356 Ti6i 6.834 154 3.33 36. 27 na=6 32 o f 84*732134**)3] nith22 L L 168334 +3-33367 6+6-2 L 10:167 10167 Ho.. Test statistics in under - x-x2 ntn, tn, 5344 + 2)

26.83 - 25.66 1.17 21.0167x/0.3333) .17 0.5821 Ecal = 2.0099 significance 1 Tabulated t at ther (10) 0.05 level of = 1. 812 conclusion - tocad a thab at 5%. L.o.s. therefore we Reject Ho and conclude that the I mean gas mileage for cars using Synthetic molor more than the by mean for the controls