document.write( "Question 431234: The annual income of residents in a county is $42,000 with a standard deviation of $10,000. Between what two values do 95% of the incomes of county residents lie? \n" ); document.write( "
Algebra.Com's Answer #299350 by robertb(5830)\"\" \"About 
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Assuming a normal distribution, then by the empirical rule, 95% of the incomes lie within two standard deviations, or between $22,000 and $62,000.
\n" ); document.write( "Assuming non-normality, and using Chebyshev's theorem, then\r
\n" ); document.write( "\n" ); document.write( "\"P%28abs%28X+-+42000%29+%3C=+k%2A10000%29+%3E=+1-1%2Fk%5E2+=+0.95\",\r
\n" ); document.write( "\n" ); document.write( "==> \"1%2Fk%5E2+=+0.05\" ==> \"k+=+2sqrt%285%29\"\r
\n" ); document.write( "\n" ); document.write( "==> \"abs%28X+-+42000%29+%3C=+20000sqrt%285%29\"
\n" ); document.write( "<==> \"42000+-++20000sqrt%285%29%3C=+X+%3C=++42000+%2B+20000sqrt%285%29\"\r
\n" ); document.write( "\n" ); document.write( "Since the left endpoint is negative, the bounds are 0 and 86,721.36.
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