# Stats

Suppose the following data are selected randomly from a population of normally distributed values.

42
51 43 48 41 57 54
39 45 48 45 39 46

Construct a 95% confidence interval to estimate the population mean.

Round the intermediate values to 2 decimal places. Round your answers to 2 decimal places, the tolerance is +/-0.05.

I do not understand how to find the 's' for the estimate of standard deviation from the sample.
n=13
xbar=46
df= 12
alpha/2= 0.025
Therefore, t= 2.179
And I am stuck...

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1. n=13
xbar=46
df= 12
alpha/2= 0.025
Therefore, t= 2.179
Sd = 5.5377
t = 2.179
(42.65, 49.35)

Z = 1.96
(42.99,49.01)

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