document.write( "Question 1152775: The scores on a college entrance examination are normally distributed with a mean of 550 and standard deviation of 100. \r
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Algebra.Com's Answer #774981 by VFBundy(438)\"\" \"About 
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z1 = \"%28575+-+550%29%2F%28100%2Fsqrt%2830%29%29\" = 1.37
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\n" ); document.write( "z2 = \"%28500+-+550%29%2F%28100%2Fsqrt%2830%29%29\" = -2.74
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\n" ); document.write( "Look up 1.37 on a z-table. You get 0.9137. This is the probability the mean score is less than 575.
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\n" ); document.write( "Look up -2.74 on a z-table. You get 0.0031. This is the probability the mean score is less than 500.
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\n" ); document.write( "To find the probability that the mean score is between 500 and 575, simply subtract 0.0031 from 0.9137. You get an answer of 0.9106.
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\n" ); document.write( "This means there is a 0.9106 probability that the mean score is between 500 and 575.
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