Question

An industrial company claims that the mean pH level of the water in a nearby river is 6.8. You randomly select 19 water samples and measure the pH of each. The data from the 19 water samples appeared to be unimodal and symmetric and had a mean pH level of 6.7 and a standard deviation of 0.24. Is this evidence that the mean pH level of the water in this river is not 6.8?

The null and alternative Hypotheses for the test are:

H_O : μ = 6.8

H_A : μ ≠ 6.8

The P-value for this test is 0.0860.

Using a significance level of 0.05 ( α = 0.05 ), give the decision for the test and the conclusion in context to answer the specific question posed.

1. Decision:
2. Conclusion in Context:

Answer 1

Decision

Here p value is 0.0860 which is greater than the significance level (0.05), therefore we accept null hypothesis at 5% LOS.

Conclusion

We accept null hypothesis it means that there is no evidence to reject the null hypothesis.

We conclude that the mean pH level of water is not significantly different than 6.8. i.e there is no evidence of the mean pH of river water is not 6.8