document.write( "Question 1207223: 3. The Edwards's Theater chain has studied its morie customers to determine how much money they spend on concessions. The study revealed that the spending distribution is approximately normally distributed with a man of 84.11 and a standard deviation of 81.37.\r
\n" ); document.write( "\n" ); document.write( "a) What percentage of customers will spend less than $2.50 on concessions\"\r
\n" ); document.write( "\n" ); document.write( "(b) What percentage of the customers will spend between 83.00 to $4.20 cm concession?\r
\n" ); document.write( "\n" ); document.write( "(c) You got free tea if you spend more than 86.00. How many people are likely to get tea if 100 people attended the movie.
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Algebra.Com's Answer #844979 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
the calculator at can help you find the answer to these questions.\r
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\n" ); document.write( "\n" ); document.write( "here are the results.\r
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\n" ); document.write( "\n" ); document.write( "this calculator can work directly off the raw scores or off the z-scores.\r
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\n" ); document.write( "\n" ); document.write( "to show you how it works off the z-scores, we'll take the second problem that calculates the probability of between 4.2 and 83.\r
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\n" ); document.write( "\n" ); document.write( "to work off z-scores, you set the mean to 0 and the standard deviation to 1.\r
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\n" ); document.write( "\n" ); document.write( "you find the z-score for 4.2 and the z-score for 83.\r
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\n" ); document.write( "\n" ); document.write( "z = (x-m)/s is the z-score formula.
\n" ); document.write( "z is the z-score.
\n" ); document.write( "x is the raw score.
\n" ); document.write( "m is the raw mean.
\n" ); document.write( "s is the standard deviation.\r
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\n" ); document.write( "\n" ); document.write( "for raw score of 4.2, formula becomes z = (4.2 - 84.11) / 81.37 = -.982057 rounded to 6 decimal places.\r
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\n" ); document.write( "\n" ); document.write( "for raw score of 83, formula becomes z = (83 - 84.11) / 81.37 = -.013641 rounded to 6 decimal places.\r
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\n" ); document.write( "\n" ); document.write( "set the calculator mean to 0 and the calculator standard deviation to 1 and find the probability of getting a z-score between -.982057 and -.013641.\r
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\n" ); document.write( "\n" ); document.write( "the results are shown below.\r
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\n" ); document.write( "\n" ); document.write( "the calculator tells you that the probability is .3325.
\n" ); document.write( "this is the same as the probability we got earlier when working directly with raw scores.
\n" ); document.write( "prior to the user of calculators, you has to get the z-score first and then work off the z-score.
\n" ); document.write( "the calculators do that work for you, but it's still useful to know how to work with the z-scores,\r
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