Find probability that sample standard deviation will exceed

Reference no: EM13318734

it is found that the lifetimes of television tubes manufactured by a company have a normal distribution with mean of 2000 hours and standard deviation of 60 hours. if 10 tubes are selected at random,find the probability that the sample standard deviation will a) not exceed 50 hours, b) lie between 50 and 70 hours.

Reference no: EM13318734

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