Respuesta :
Answer:
(0.5864, 7.2136)
Step-by-step explanation:
Given that for a simple random sample of 50 Buffalo residents the mean is 22.5 miles a day and the standard deviation is 8.4 miles a day. For an independent simple random sample of 40 Boston residents the mean is 18.6 miles a day and the standard deviation is 7.4 miles a day
Group I Group II
Mean 22.5 18.6
STd dev 8.4 7.4
n 50 40
Mean difference =[tex]22.5-18.6=3.9[/tex]
a) point estimate for mean difference = 3.9
b) Std deviation pooled = 7.9723
pooled df = 88
Confidence interval 95% [tex]= (0.5864, 7.2136)[/tex]