Hey guys please I need help with those problems and I apprec

Hey guys please I need help with those problems and I appreciate explinations

Problems 62(a,b,i,ii,iii), 63(a,b,i,ii,iii), 64(a,b,i,ii,iii),

problem 9.74

Problem 86, 87

Solution

9.62

a)

Here, we use the Z STATISTIC, because we have a large sample size, n = 38 > 30.

Also, we know the population standard deviation, sigma = 15.

b)

Using table/technology, as this is a left tailed test, then

i. alpha = 0.01

The rejection region is thus

z < -2.326347874 [ANSWER]

****

ii. alpha = 0.025

The rejection region is thus

z < -1.959963985 [ANSWER]

****

iii. alpha = 0.05

The rejection region is thus

z < -1.644853627 [ANSWER]

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