Question

A supplier of digital memory cards claims that less than 1% of the cards are defective. In a random sample of600 memory cards, it is found that 3% are defective, but the supplier claims that this is only a sample fluctuation. At the 0.01 level of significance, test the supplier's claim that less than 1% are defective. Use the p-value method.

Answer 1

Answer:

The  decision rule is

Fail to reject the null hypothesis

The conclusion is  

    The is no sufficient evidence to support the claim that the less than 1% of the cards are defective

Step-by-step explanation:

From the question we are told that

     The sample size is  $n = 600$

      The population proportion of defective samples is p =  0.01

       The sample proportion of defective samples is  $\^ p = 0.03$

       The level of significance is $\alpha = 0.01$

       

The null hypothesis is $H_o : p = 0.01$

The alternative hypothesis is  $H_a: p < 0.01$

      Generally the test statistics is mathematically represented as

                  $t = \frac{\^ p - p }{ \sqrt{ \frac{p( 1 - p )}{n} } }$      

=>              $t = \frac{0.03 - 0.01 }{ \sqrt{ \frac{0.01( 1 - 0.01 )}{600} } }$

=>              $t = 0.00406$

From the z table  the area under the normal curve to the left corresponding to  0.00406   is

         $p-value = P(Z < 0.00406 ) = 0.50162$

comparing the p-valve and the level of significance we see that the

           $p-value > \alpha$     hence  

The  decision rule is

Fail to reject the null hypothesis

The conclusion is  

    The is no sufficient evidence to support the claim that the less than 1% of the cards are defective