A sample of 14 randomly selected commuters in Chicago showed the average of the commuting times...
Homework Answers
As confidence interval not specified, we assume it for 95%
n = 14
mean = 33.2
t-value of 95% CI = 2.1604
std. dev. = 8.3000
SE = std.dev./sqrt(n)
= 8.3/sqrt(14)
= 2.21827
ME = t*SE
= 2.1604*2.21827
= 4.79228
Lower Limit = Mean - ME = 33.2 - 4.79228 = 28.40772
Upper Limit = Mean + ME = 33.2 + 4.79228 = 37.99228
95% CI (28.4077 , 37.9923)
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sample of 14 randomly selected commuters in Chicago showed the
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