Answer:
The calculated value t= 3,947 > 2.0301 at 0.05 level of significance ( two tailed test) with 35 degrees of freedom.
Null hypothesis is rejected
There is no strong evidence that they have attained their fuel economy goal.
Step-by-step explanation:
<u>Step (i):</u>-
A company with a large fleet of cars hopes to meet the goal of 38.2 mpg or better for their fleet of cars.
Population mean 'μ' = 38.2mpg
Given the gasoline usage for 36 company trips chosen at random, finding a mean of 40.20 mpg and a standard deviation of 3.04 mpg.
Sample size 'n' = 36
mean of the Sample 'x⁻' = 40.20mpg
standard deviation of the Sample 'S' = 3.04 mpg.
<u>Step(ii)</u>:-
Null hypothesis: H₀: 'μ' = 38.2mpg
Alternative hypothesis: H₁: 'μ' ≠ 38.2mpg
Level of significance ∝=0.05
The test of hypothesis
The degrees of freedom ν= n-1 = 36-1 =35
The tabulated value t₀.₀₅ = 2.0301 at 0.05 level of significance ( two tailed test) with 35 degrees of freedom.
The calculated value t= 3,947 > 2.0301 at 0.05 level of significance ( two tailed test) with 35 degrees of freedom.
Null hypothesis is rejected
<u>Conclusion:</u>-
There is no strong evidence that they have attained their fuel economy goal.