Help

Some manufacturers claim that non-hybrid sedan cars have a lower mean miles-per-gallon (mpg) than hybrid ones. Suppose that consumers test 225 hybrid sedans and get a mean of 25.25 mpg with a standard deviation of 5.25 mpg. Also, 245 non-hybrid sedans get a mean of 24.25 mpg with a standard deviation of 6.75 mpg. Suppose that both populations are known to be normal distributed. Conduct a hypothesis test to evaluate the manufacturers' claim. Test at a 8% level of significance. Let population 1 denote non-hybrids and population 2 denote hybrids. (a) HQ: M1 Click for List H2 (b) Ha: M1 Click for List H2 (c) In words, state what your random variable represents. The random variable is the Click for List miles per gallon of non-hybrid sedans and hybrid sedans. (d) Select the distribution to use for the test. O X1 - X2 ~ N [o, /] O X1 - X2 ~ N [ #1 - 12, 0 ] o taf O X~ N [ M, o ) O X 1 - X 2 ~ N [ / , o ] (e) What is the test statistic? Round your answer to three decimal places Test statistic = Number (f) What is the p-value? Round your answer to three decimal places. p-value = Number (g) Select the correct graph of this situation. * - X 2 X - X2 i. Alpha: Number li. Decision: Click for List the null hypothesis. iii. Reason for decision: p-value Click for List iv. Conclusion: There Click for List - sufficient evidence to conclude that the mean miles per gallon of non-hybrid sedans is less than that of hybrid sedans