A high school counselor needs to specify whether the teenage pregnancy rate at her school is disimilar from the rate nationwide. She knows that the rate nationwide is 15 %. She randomly selects 80 female students from her high school.  She serach that 9 out of 80 students are either pregnant now or have been pregnant lastly.

a.    What statistical test should be used to examine the data? The z test should be used to examine the data.

b.    Identify H0 and Ha for this study
Ho: p = 0.15
Ha: p not equal 0.15

c.    Conduct the appropriate analysis
z= (phat - p) /sqrt(p*(1-p)/N)
z=(9/80 - 0.15)/sqrt(0.15*0.85/80)
z= -0.933933

d.    Should H0 be devorted? What should the researcher conclude? The Ho can not be rejected or the null hypothesis is not rejected.