Question 1026355
Chlorine concentration in a municipal water supply is a uniformly distributed random variable that ranges between 0.74 ppm and 0.98 ppm.
Note: base = 0.98-0.74 = 0.24 height = 1/0.24 = 4.17 
Calculate the mean chlorine concentration.:: (0.74+0.98)/2 = 0.86
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Chlorine concentration in a municipal water supply is a uniformly distributed random variable that ranges between 0.74 ppm and 0.98 ppm. 
Calculate the standard deviation.:: (0.98-0.74)/6 = 0.08
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Chlorine concentration in a municipal water supply is a uniformly distributed random variable that ranges between 0.74 ppm and 0.98 ppm. 
Calculate the probability that the chlorine concentration will exceed 0.80 ppm
z(0.8-0.86)/0.08 = -0.75 = (3/4)std below the mean
Ans: 0.50 + (0.75)(1/6) = 0.625
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Chlorine concentration in a municipal water supply is a uniformly distributed random variable that ranges between 0.74 ppm and 0.98 ppm. 
Calculate the probability that the chlorine concentration will be between 0.80 ppm and 0.90 ppm
(0.9-0.8) = 0.1(1/6) = 0.0167
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Cheers,
Stan H.
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