## High-power experimental engines are being developed by the Stevens Motor Company for use in its new sports coupe. The engineers have calcula

High-power experimental engines are being developed by the Stevens Motor Company for use in its new sports coupe. The engineers have calculated the maximum horsepower for the engine to be 580HP. Sixteen engines are randomly selected for horsepower testing. The sample has an average maximum HP of 610 with a standard deviation of 55HP. Assume the population is normally distributed. Step 2 of 2 : Use the confidence interval approach to determine whether the data suggest that the average maximum HP for the experimental engine is significantly different from the maximum horsepower calculated by the engineers.

## Answers ( )

Answer:The calculated value t = 2.18 > 1.753 at 5% level of significance.we accepted the Alternative hypothesisHence the data suggest that the average maximum HP for the experimental engine is significantly different from the maximum horsepower calculated by the engineers.Step-by-step explanation:Step(i):–Given sample size ‘n’ =16Given data the engineers have calculated the maximum horsepower for the engine to be 580HPMean of the Population ‘μ’ = 580HPMean of the sample size ‘x⁻’ =610The sample standard deviation ‘S’ = 55HPNull hypothesis: H₀:There is no significant difference between the average maximum HP for the experimental engine and maximum horsepower calculated by the engineers.That is H₀: x⁻ = μAlternative hypothesis: H₁: x⁻ ≠ μStep(ii):-The test statistict = 2.18The degrees of freedom ν=n-1 =16-1=15The tabulated valuet₀.₉₅ = 1.753The calculated value t= 2.18 > 1.753 at 95% of level of significanceThe null hypothesis is rejectedwe accepted the Alternative hypothesisConclusion:-Hence the data suggest that the average maximum HP for the experimental engine is significantly different from the maximum horsepower calculated by the engineers.