Homework Answers
Answer:
Given,
n = 20
xbar = 32215
s = sqrt(3116)
= 55.82
degree of freedom = n - 1
= 20 - 1
= 19
alpha = 0.01/2 = 0.005
Here the t value t(0.005,19) = 2.86
Now interval = xbar +/- t*s/sqrt(n)
= 32215 +/- 2.86*55.82/sqrt(20)
= 32215 +/- 35.6978
= (32215 - 35.6978 , 32215 + 35.6978)
= (32179.3 , 32250.7)
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