Practice Test 3 Answers

 

1)      H_o: m = 69 (claim)                                

H_a: m 69                                         

Two-tail                                                  

Ztest                                                

                                        

Fail to reject H_o                                    

Data supports the claim               

that the mean is 69.                                  

2)      ZInterval                                           .

            m                                   8) 2-PropZInt

3)      H_o: m = 2.0                                               0.02   0.38

H_a: m > 2.0 (claim)                               

One-tail                                                 

23                                                           

                                              

TTest                                                      

                                           

Reject H_o                                                                

Data supports the claim                

that the mean GPA is                                

greater than 2.0                                   

4)      TInterval                                                     

 m                                     

                                                                              

                                                                                              

                                                                        

                                                                  

                                                                      

                                                                

                

                                                              11) 2-SampTInt

                                                          

6)      2-SampTInt (Pooled)

0.1 m_d  9.9

 

 

                                                                                   

 

 

 

14) H_o: p = .058

      H_a: p < .058 (claim)

      One-tail

     

     

      Reject H_o

      The data supports the claim that the failure rate is now lower.

15) H_o: p = .09 (claim)

      H_a: p .09

      Two-tail

     

     

      Fail to reject H_o

      The data supports the claim that 9% of college students carry such weapons.

16) H_o: p = .2

      H_a: p > .2 (claim)

      One-tail

      z = 1.645

      z = 1.73

      Reject H_o

     The data supports the claim that more than 20% watch “60 Minutes”.

17) a) .52         b) 7.08  m  8.12

18) a) 6.7         b) 97.3  m  110.7

19) a) ZInterval            b) $41768  m  $45640

20) a) 1-PropZInt         b)

21) a) TInterval            b) 72.2  m  79.8