Question

Elementary Statistics by Mario Triola, 13th edition Chapter 8.1.17

The test statistic of z=2.23 is obtained when testing the claim that p>0.3

a. Identify the hypothesis test as being​ two-tailed, left-tailed, or​ right-tailed.

b. Find the​ P-value.

c. Using a significance level of α=0.05​, should we reject H0, or should we fail to reject H0​?

Answer 1

Answer:

a)

Given,

z = 2.23

p > 0.3

Here we have to identify the test hypothesis

It is given that

p > 0.3

So by observing we can say that it is a right tailed test

b)

To give the p value

Given,

z = 2.23

consider,

P(z > 2.23) = 0.0128737 [since it is right tailed]

P(z > 2.23) = 0.0129 [since from z table]

c)

Given,

significance level = 0.05

Here we observed that p value is less than significance level. So that we can reject the null hypothesis i.e., Ho

i.e.,

0.0129 < 0.05

So hence we reject the null hypothesis Ho