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In: Statistics and Probability

A certain type of thread is manufactured with a mean tensile strength is 78.3kg, and a...

A certain type of thread is manufactured with a mean tensile strength is 78.3kg, and a standard deviation is 5.6kg. Assuming that the strength of this type of thread is distributed approximately normal, find: a) The probability that the mean strength of a random sample of 10 such thread falls between 77kg and 78kg. b) The probability that the mean strength greater than 79kg. c) The probability that the mean strength is less than 76kg. d) The value of X to the right of which 15% of the mean computed from random samples of size 10 would fall.

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orchestra answered 2 years ago
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