document.write( "Question 165391: find the percent of the total area under the standard curve between the given z-scores. z = 2.18 and z = 3.45 \n" ); document.write( "
Algebra.Com's Answer #121983 by gonzo(654)\"\" \"About 
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between z = 2.18 and z = 3.45 area under the curve is .014348
\n" ); document.write( "there's an online calculator that helps you to solve problems like this.
\n" ); document.write( "it is at the following internet address:
\n" ); document.write( "http://davidmlane.com/hyperstat/z_table.html
\n" ); document.write( "check it out.
\n" ); document.write( "the normal curve has a mean of 0 and a standard deviation of 1.
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\n" ); document.write( "here's a definition of z score that might be helpful.
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\n" ); document.write( "Z scores are a special application of the transformation rules. The z score for an item, indicates how far and in what direction, that item deviates from its distribution's mean, expressed in units of its distribution's standard deviation. The mathematics of the z score transformation are such that if every item in a distribution is converted to its z score, the transformed scores will necessarily have a mean of zero and a standard deviation of one.\r
\n" ); document.write( "\n" ); document.write( "Z scores are sometimes called \"standard scores\". The z score transformation is especially useful when seeking to compare the relative standings of items from distributions with different means and/or different standard deviations.\r
\n" ); document.write( "\n" ); document.write( "Z scores are especially informative when the distribution to which they refer, is normal. In every normal distribution, the distance between the mean and a given Z score cuts off a fixed proportion of the total area under the curve. Statisticians have provided us with tables indicating the value of these proportions for each possible Z score.
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