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Alex
3 years ago
12

A shoe manufacturer was investigating the weights of men's soccer cleats. He felt that the weight of these cleats was less than

the average weight of 10 ounces. After a random sample of 13 pairs of cleats, he found that sample mean was 9.63 and the standard deviation was .585. At a significance level of .05, can it be concluded that the researcher was correct?
Show work
Mathematics
1 answer:
aleksklad [387]3 years ago
6 0

Answer:

 The conclusion is that the researcher was correct

Step-by-step explanation:

From the question we are told that

     The sample size is  n =  13

    The sample mean is  \= x =  9.63

     The standard deviation is  s =  0.585

      The significance level is  \alpha  =  0.05

The Null Hypothesis is  H_o :  \mu = 0

The Alternative  Hypothesis  is  H_a =  \mu < 10

The test statistic is  mathematically represented as

          t =  \frac{\= x - \mu }{\frac{s}{\sqrt{n} } }

Substituting values

          t =  \frac{9.63  - 10 }{\frac{0.585}{\sqrt{13} } }

         t =  -  2.280

Now the critical value for \alpha is  

     t_{\alpha } = 1.645

This obtained from the critical value table

  So comparing the critical value of alpha and the test value we see that the test value is less than the critical value so the Null Hypothesis is rejected

 The conclusion is that the researcher was correct

 

 

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