Question 828988
Peter Pine is doing his budget. He discovers that he has spent an average of $225.00 a month on entertainment for the year with a standard deviation of $75.00. What percent of his monthly expenses for this category would he expect to fall between $60.00 and $390.00? 
The z for $60.00 = (60-225)/75 = -2.2
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The percent of area between z = 0 and z = -2.2 = 0.4861
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The z for $390.00 = 2.2
The percent of area associated with $390.00 = +0.4861
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Adding the two percentages together, 
Peter calculates his answer to be 2*0.4861 = 0.9722
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Cheers,
Stan H.
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