The marketing manager of a firm that produces laundry products decides to test market a new laundry product in each of the firm's two sales regions. He wants to determine whether there will be a difference in mean sales per market per month between the two regions. A random sample of 12 supermarkets from Region 1 had mean sales of 79.8 with a standard deviation of 8.8. A random sample of 17 supermarkets from Region 2 had a mean sales of 85.2 with a standard deviation of 8.3. Does the test marketing reveal a difference in potential meal sales per market in Region 2? Use a signifiance level of a = 0.02 for the test. State the null and alternative hypotheses for the test and find the test statistic.

Respuesta :

Answer:

The null hypothesis is  [tex]H_o: \mu_1 = \mu_2[/tex]

The  alternative hypothesis is  [tex]H_1 : \mu_1 \ne \mu_2[/tex]

The test statistics is  [tex]t = -1.667[/tex]

Step-by-step explanation:

From the question we are told that

  The first sample size is  [tex]n_1 = 12[/tex]

   The  first sample  mean is  [tex]\= x_1 = 79.8[/tex]

    The first standard deviation is  [tex]\sigma _1 = 8.8[/tex]

   The second sample  size is  [tex]n_2 = 17[/tex]

    The  second  sample  mean is  [tex]\= x_2 = 85.2[/tex]

    The second  standard deviation is  [tex]\sigma _2 = 8.3[/tex]

The null hypothesis is  [tex]H_o: \mu_1 = \mu_2[/tex]

The  alternative hypothesis is  [tex]H_1 : \mu_1 \ne \mu_2[/tex]

Generally the test statistics is  mathematically represented as  

                 [tex]t = \frac{\= x_ 1 - \= x_2 }{ \sqrt{ \frac{\sigma_1^2 }{n_1 } +\frac{\sigma_2^2 }{n_2} } }[/tex]

   =>          [tex]t = \frac{ 79.8 - 85.2 }{ \sqrt{ \frac{8.8^2 }{12} +\frac{ 8.3^2 }{17} } }[/tex]

=>                [tex]t = -1.667[/tex]