document.write( "Question 811763: Can I please get help to answer the following question with full working.\r
\n" ); document.write( "\n" ); document.write( "The sales of a new electronic gadget are growing exponentially such that a
\n" ); document.write( "total of 10000 gadgets were sold in 2000 and 82700 gadgets were sold in
\n" ); document.write( "2002. If this trend continues, in what year will sales of the gadget reach or
\n" ); document.write( "exceed 500 000?
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Algebra.Com's Answer #488881 by josgarithmetic(39617)\"\" \"About 
You can put this solution on YOUR website!
Take year 2000 to be time of 0, for convenience.\r
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\n" ); document.write( "\n" ); document.write( "\"y=10000e%5E%28kt%29\" for t as time in years since 2000, y is the sales count of items sold at time t, and k is a constant.\r
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\n" ); document.write( "\n" ); document.write( "Solve symbolically for k.
\n" ); document.write( "\"ln%28y%29=ln%2810000%29%2Bkt%2Aln%28e%29\"
\n" ); document.write( "\"ln%28y%29-ln%2810000%29=kt\"
\n" ); document.write( "\"k=%28ln%28y%29-ln%2810000%29%29%2Ft\"\r
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\n" ); document.write( "\n" ); document.write( "Use the point for year 2002, for t=2, to get a value for k.
\n" ); document.write( "\"k=%28ln%2882700%29-ln%2810000%29%29%2F2\"
\n" ); document.write( "\"k=2.1126%2F2\"
\n" ); document.write( "\"highlight%28k=1.056%29\"\r
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\n" ); document.write( "\n" ); document.write( "The model equation is \"highlight%28y=10000e%5E%281.056%2At%29%29\"-----\r
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\n" ); document.write( "\n" ); document.write( "Your question to answer is, find t for y=500000.
\n" ); document.write( "Looking back at solving for k, the step was found,
\n" ); document.write( "\"ln%28y%29-ln%2810000%29=kt\"
\n" ); document.write( "from which we can easily step to
\n" ); document.write( "\"t=%28ln%28y%29-ln%2810000%29%29%2Fk\"
\n" ); document.write( "and then substituting for y, and k,
\n" ); document.write( "\"t=%28ln%28500000%29-ln%2810000%29%29%2F1.056\"
\n" ); document.write( "\"highlight%28t=3.704%29\" years since 2000, or some late in the year 2003, or very early in year 2004.\r
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\n" ); document.write( "\n" ); document.write( "Think about that time value. 2000+3.7=2003.7, which could potentially be early in year 2004.
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