The metropolitan airport commission is considering the establishment of limitations on noise pollution around a local airport. At the present time, the noise level per jet takeoff ine one neighborhood near the airport is approximately normally distributed with a mean of 100 decibels and a standard deviation of 6 decibels.

a. What is the probability that a randomly selected jet will generate a noise level greater than 108 decibels in this neighborhood?

b. What is the probability that a randomly selected jet will generate a noise level of exactly 100 decibels?

c. Suppose a regulation is passed that requires jet noise in this neighborhood to be lower than 105 decibels 95% of the time. Assuming the standard deviation of the noise distribution remains the same, how much will the mean level have to be lowered to comply with the regulation?

Answer rating: 100% (QA)

a ZXmeanStandard deviation1081006133 P Z133 0091759198 Look at the normal distribution ... View the full answer