document.write( "Question 805876: The number of Americans (in thousands) who are expected to be over 100 years old in year x is approximated by:
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\n" ); document.write( " F(x) = .27x2 + 3.52x + 51.78\r
\n" ); document.write( "\n" ); document.write( "where x= 0 corresponds to 2000 and the formula is valid through 2045.
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\n" ); document.write( "a) Find a formula giving the rate of change in the number of Americans over 100 years old.\r
\n" ); document.write( "\n" ); document.write( "b) What is the rate of change in the number of Americans expected to be over 100 years old in the year 2015?
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Algebra.Com's Answer #485614 by KMST(5328)\"\" \"About 
You can put this solution on YOUR website!
The numbers that come from that equation seem a bit too high, but I like them.
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\n" ); document.write( "I assume this is a problem from calculus class, that you are expected to calculate the derivative of \"F%28x%29\" , and that you know how to calculate derivatives of polynomials.
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\n" ); document.write( "With those assumptions in mind,
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\n" ); document.write( "a) \"dF%2Fdx=0.27%282x%29%2B3.25=0.54x%2B3.25\"
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\n" ); document.write( "b) For the year 2015, \"x=15\" and
\n" ); document.write( "\"dF%2Fdx=0.54%2A15%2B3.25=11.35\"
\n" ); document.write( "meaning that the number of centenarians would be increasing by 11,890 a year.
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