8.75

  1. Under H0: m=50. Therefore sample mean has an approximately normal distribution with mean 50 and standard deviation of sample mean=
  2. Sample mean has an approximately normal distribution with mean 45 and standard deviation of sample mean=
  3. Reject H0 if z<1.282 which implies
  4. Power=1-.2358=.7642

 

8.80

a.

Type II Error

b.

Type I Error

c.

8.87

(In the text)

8.88

To determine if the variance of birth weights of babies delivered by cocaine-dependent women is less than 200,000, we test

8.105 & 8.117 are in the Text