The table gas mileages in miles in miles per gallon of eight cans with and without a fuel additive. At a =0.10 is there enough evidence to conclude that the fuel additive improved gas mileage.
Cars 1 2 3 4 5 6 7 8
Gas mileage without additive 22.3 24.3 24.3 21.6 21.1 22.9 25.7 20.9
Gas mileage with fuel additive 23.0 26.9 25.0 22.7 21.8 24.6 27.4 23.5
a). Identify claim and state H0 and Ha,
b). Let ud be the hypothesized mean of the car's gas mileage without additive minus their gas mileage with additive. State the Ho and Ha.
c) Find the critical values indentify the rejection region.
d). calculate d and sd(3 decimal places).
e). Use the t-test to find the standardized test statistic t
f). decide whether to reject or fail to reject the null.