Thread: Distribution and probability

The parent distribution of x is normal with mean 80 and std. dev. 9

sample size n = 25, mean (pop) of mean (samp) = 80, std dev (pop) of mean (samp) = 9/5 = 1.8
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x = sample mean

find
A. P(62 < x < 80)
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B. P(71 < x < 77)
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C. x' such that P(x > x') = .05


Thanks in advance if anyone can help me with this

I did these earlier, see
http://www.mathhelpforum.com/math-he...nt-sample.html
but they asked the wrong question for part 3, it's easy to fix it, just use 1.645 instead of -1.645

Originally Posted by matheagle

I did these earlier, see
http://www.mathhelpforum.com/math-he...nt-sample.html
but they asked the wrong question for part 3, it's easy to fix it, just use 1.645 instead of -1.645

Therefore, thread closed.