Answer :
Answer:
A
The correct option is C
B
The value of z-test is [tex]z = -2.267[/tex]
Step-by-step explanation:
From the question we are told that
The null hypothesis [tex]H_o : p = 0.22[/tex]
The alternative hypothesis [tex]H_a : p \ne 0.22[/tex]
The level of significance is [tex]\alpha = 0.01[/tex]
The sample proportion is [tex]\^ p = 0.15[/tex]
The sample size is n = 180
Generally from central limit theorem
if np and nq are > 5 then normal sampling distribution can be used
So
np = 180 * 0.22 = 39.6 > 5
and
nq = 180 * (1 -0.22) = 140.4 > 5
So normal sampling distribution can be used
Generally the z-test is mathematically represented as
[tex]z = \frac{\^ p - p }{ \sqrt{\frac{ p(1- p ) }{n } } }[/tex]
=> [tex]z = \frac{ 0.15 - 0.22 }{ \sqrt{\frac{ 0.2(1- 0.22 ) }{ 180 } } }[/tex]
=> [tex]z = -2.267[/tex]