Please be thorough in your work and explain using English wo
Please be thorough in your work and explain using English words as well. Show all work
Solution
(1) Given a=0.01, Z(0.01) =2.33 (from standard normal table)
2.33= (xbar-mu)/(s/vn) = (xbar-4)/(5/sqrt(25))
--> 2.33 = xbar-4
So xbar = 4+2.33=6.33
So the probability of Type II error is
P(X>6.33) = P(Z>(6.33-2)/(5/sqrt(25))
=P(Z>4.33) =0 (from standard normal table)
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(2) Z(0.05/2)= Z(0.025) = 1.96 (from standard normal table)
Z(0.05)=1.65 (from standard normal table)
So n=S^2*(Z(1-a/2) + Z(1-0.95))^2/(4-2)
=5^2*(1.96+1.65)^2/2
=162.9013
Take n=163

