A manufacturer of chocolate chips would like to know whether its bag filling machine works correctly at the 420 gram setting. It is believed that the machine is underfilling the bags. A 49 bag sample had a mean of 413 grams. Assume the population variance is known to be 676 . A level of significance of 0.1 will be used. Find the P-value of the test statistic. You may write the P-value as a range using interval notation, or as a decimal value rounded to four decimal places.

Respuesta :

Answer:

The  value is  [tex]p-value = 0.0297[/tex]

Step-by-step explanation:

From the question we are told that

   The population mean is  [tex]\mu = 420 \ g[/tex]

   The The  sample  size is [tex]n = 49[/tex]

    The sample  mean is  [tex]\= x = 413 \ g[/tex]

    The  population variance is   [tex]\sigma^2 = 676[/tex]

Generally the population standard deviation is  mathematically represented as

     [tex]\sigma = \sqrt{\sigma^2 }[/tex]

     [tex]\sigma = \sqrt{676}[/tex]

     [tex]\sigma = 26[/tex]

The null hypothesis is  [tex]H_o : \mu = 420 \ g[/tex]

The  alternative  hypothesis is [tex]H_a : \mu < 420 \ g[/tex]

 Generally the test statistics is mathematically represented as

          [tex]z = \frac{ \= x - \mu }{ \frac{ \sigma }{\sqrt{n} } }[/tex]

=>        [tex]z= \frac{ 413 - 420 }{ \frac{ 26 }{\sqrt{49} } }[/tex]

=>       [tex]z = -1.884[/tex]

The  p-value is  obtained from the z-table table and the value is  

       [tex]p-value = P(Z < -1.885) = 0.029715[/tex]

       [tex]p-value = 0.0297[/tex]