True/false:
If the sample size is n = 21 and the population standard deviation is unknown, the critical value t needed to construct a 90% confidence level for μ is t = 1.721.
n = 21
Degrees of freedom = df = n - 1 = 21 - 1 = 20
At 90% confidence level the t is ,
= 1 - 90% = 1 - 0.90 = 0.1
/ 2 = 0.1 / 2 = 0.05
t /2,df = t0.05,20 = 1.724 ( using student t table)
false
True/false: If the sample size is n = 21 and the population standard deviation is unknown,...
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