Respuesta :
Answer:
At 95% confidence limits for the true difference between the average Miles per Gallon for the two models is -1.8210 to 4.1789
Yes 95 % confidence means that there's conclusive evidence to indicate that one model gets a higher MPG than the other.
Step-by-step explanation:
Model A Model B
Sample Size 50 55
Sample Mean x` 32 35
Sample Variance s² 9 10
At 95 % confidence limits are given by
x1`-x2` ± 1.96 [tex]\sqrt{\frac{s^{2} }{n1} +\frac{s^{2}}{n2} }[/tex]
Putting the values
32-35 ± 1.96 [tex]\sqrt\frac{9}{50}+\frac{10}{55}[/tex] ( the variance is the square of standard deviation)
-3 ± 1.96 [tex]\sqrt{ \frac{495+500}{2750}[/tex]
-3 ± 1.96( 0.6015)
-3 ± 1.17896
-1.8210; 4.1789
Thus the 95% confidence limits for the true difference between the average Miles per Gallon for the two models is -1.8210 to 4.1789.
Yes 95 % confidence means that there's conclusive evidence to indicate that one model gets a higher MPG than the other.