Question 933890
 μ= 184 seconds, σ= 55 sec.  {{{z = blue(x - 184)/blue(55)}}}
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Person selected:
P( x > 230) =   P(z > 46/55) = normalcdf(46/55, 100) = .2015  0r 20.15%
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P( .10 < x < .90) = P( -1.2816 < z < 1.2816) = normalcdf(-1.2816, 1.2816) = .8000  0r 80%
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 Using a TI calculator 0r similarly a Casio fx-115 ES plus
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Recommend Using stattrek.com to check  Results
until You are familiar with Using Your Calculator.