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makeda123
A laboratory weighs filters from a coal mine to measure the amount of dust in the mine atmosphere. Repeated measurements of the weight of dust on the same filter vary normally with a standard deviation of 0:08 milligram (mg) because the weighing is not perfectly precise. The dust on a particular filter actually weighs 123 mg. Repeated weighings will then have the normal distribution with mean 123 mg and standard deviation 0.08 mg. a) The laboratory reports the mean of 3 weighings. What is the distribution of this mean? b) What is the probability that the laboratory reports a weight of 124 mg