A random sample of 175 measurements possessed a mean x¯=8.2 and a standard deviation s = .79.

a. Test H0:μ=8.3 against Ha:μ8.3Use a=0.05

Short Answer

Expert verified

⦁ The Z-statistic does not fall into the rejection region. So, we fail to reject the

null hypothesis.

Step by step solution

01

Given Information

The sample size, n=175

The mean,x¯=8.2

The standard deviation, s=0.79

02

State the concept used in the test.

The statistical hypothesis test is used here. A statistical hypothesis is a statement about the numerical value of a population parameter.

03

Compute the hypothesis test H0:μ=8.3 against Ha:μ≠8.3 at the significance level a=0.05 

The null and alternative hypothesis are:

H0:μ=8.3Ha:μ8.3

The significance level,a=0.05

The test statistic is computed as:

Z=x¯-μs/n=8.2-8.30.79/175=-0.10.0597=-1.675

This is a two-tailed test. So, the Za2 obtained from the standard normal table is 1.96.

Here, z<za2-1.675<1.96. So, we fail to reject the null hypothesis.

Hence, the Z-statistic does not fall into the rejection region. So, we fail to reject the null hypothesis.

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