a)
Since sample size is sufficiently large, that is n ( = 58) > 30 ,
Yes, condition that is normally distributed is satisfied.
b)
Margin of error = Z/2 * / sqrt(n)
= 2.576 * 18.6 / sqrt(58)
= 6.29
c)
Margin of error = Z/2 * / sqrt(n)
= 2.576 * 18.6 / sqrt(245)
= 3.06
Consider a population with a known standard deviation of 18.6. In order to compute an interval estimate for the populat...
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