Question
In: Statistics and Probability
Most water-treatment facilities monitor the quality of their drinking water on an hourly basis. One variable...
Most water-treatment facilities monitor the quality of their
drinking water on an hourly basis. One
variable monitored is pH, which measures the degree of alkalinity
or acidity in the water.
A pH below 7.0 is acidic, one above 7.0 is alkaline, and a pH of
7.0 is neutral.
One water-treatment plant has a target pH of 8.5(Most try to
maintain a slightly alkaline level.) The mean
and standard deviation of 1 hour’s test results, based on 17 water
samples at this plant,
are: x = 8.42 s = .16
Does this sample provide sufficient evidence that the mean pH level
in the water differs from 8.5?
Solutions
orchestra answered 1 year agoRelated Solutions
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