Question

Emissions of sulfur dioxide by industry set off chemical changes in the atmosphere that result in acid rain. The acidity of liquids is measured by pH on a scale from 0 to 14. Distilled water has pH of 7.0 and lower pH values indicate acidity. The pH of rain at one location varies among rainy days according to a normal distribution with mean 5.43 and standard deviation 0.52.

c) Normal rain is somewhat acidic, so acid rain is sometimes defined as rain fall with a pH below 5.0. What proportion of rainy days have rainfall with pH below 5.0? Calculate the probability using a z-score and the s

Answer 1

@mathmale

Answer 2

Is that right?

Answer 3

@Zarkon

Answer 4

Am I solving this correctly using the table? So X = 5, sigma = 0.52, mu = 5.43

I need to solve for Z then use the table I posted

Answer 5

For clarification: You're to calculate the area under the standard normal curve which lies to the left of x=5.

To do this, calculate the "z-score."

Next, look up the z-score in the table and copy down the decimal fraction that represents it. That fraction is the result you want.

Where are you now in this process?

Answer 6

Type in the formula for "z-score."

Answer 7

My result for that is a negative quantity between 0 and -1.

Answer 8

I got Z = -0.8269, looking in the back of the table which is posted I got 0.2061 <==== what does this mean?

Answer 9

what does 0.2061 mean?