document.write( "Question 378075: Suppose the heights of 18-year-old men are approximately normally distributed, with mean 69 inches and standard deviation 2 inches. \r
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\n" ); document.write( "\n" ); document.write( "(b) If a random sample of sixteen 18-year-old men is selected, what is the probability that the mean height x is between 68 and 70 inches? \n" ); document.write( "

Algebra.Com's Answer #268702 by ewatrrr(24785) $\"\"$ $\"About$

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document.write( "Hi
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document.write( "a)probability that an 18-year-old man selected at random is between 68 and 70 inches tall
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document.write( " = .5  NORMSDIST(.5)  = .6915
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document.write( "= -.5  NORMSDIST(-.5) = .3085
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document.write( "P(-.5 < z > .5) = .6915 - .3085 = .3829  Or 39.29%\r
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document.write( "b)random sample of sixteen 18-year-old men is selected
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document.write( "test statistic = 
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document.write( " z= 1/(2/4)  =  2  NORMSDIST(2)  = .6915 = .9773
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document.write( " z = -1/(2/4)= -2  NORMSDIST(-2)  = .6915 = .0228
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document.write( "P(-2 < z > 2) = .9973 - .0228 = .9545  Or 95.45%
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