30) The random variable X is distributed normally with mean 82.6 and standard deviation $sigma$. The mean a random sample of size $n = 20$ is $ar{X}$. Given that $P(ar{X} > 80) = 0.75$, Find the value of $sigma$. A) 302.76 B) 15.21 C) 17.4 D) 3.9
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6 and an unknown standard deviation σ. 2) We also know that the mean of a random sample of size n = 20 is X̄. 3) We are given that P(X > 80) = 0.75. 4) We need to find the value of σ. Show more…
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