The following 96% C.I. for μ was obtained from a sample of 15 observations (population variance is known) (-2257.6960,1075.2183)
1. what is x bar?
2. what is sigma?
xbar - t*sigma/sqrt(n) = -2257.6960
xbar + t*sigma/sqrt(n) = 1075.2183
2xbar = -1182.4777
xbar = -591.2389
here t = 2.2638
t*sigma/sqrt(n) = 1075.2183 + 591.2389
sigma/sqrt(n) = 1666.4572/2.2638
sigma/sqrt(n) = 736.1327
sigma = 736.1327*sqrt(15)
sigma = 2851.0297
The following 96% C.I. for μ was obtained from a sample of 15 observations (population variance...
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