document.write( "Question 1032586: Sandy is tracking the performance of one of Atlantic Cycles' savings accounts. $10,000 was deposited into this account which earns 2.25% interest compounded continuously. How many years will it take until the account balance doubles if no withdrawals or additional deposits are made? \r
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\n" ); document.write( "\n" ); document.write( "I set up problem as: $20,000= $10,000*2.718281828459(.0225x). I got 32 years as answer but this was wrong. Please help. Thank you. \n" ); document.write( "
Algebra.Com's Answer #647263 by MathTherapy(10552)\"\" \"About 
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Sandy is tracking the performance of one of Atlantic Cycles' savings accounts. $10,000 was deposited into this account which earns 2.25% interest compounded continuously. How many years will it take until the account balance doubles if no withdrawals or additional deposits are made? \r
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\n" ); document.write( "\n" ); document.write( "I set up problem as: $20,000= $10,000*2.718281828459(.0225x). I got 32 years as answer but this was wrong. Please help. Thank you.
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Future value (A), and present value (P) amounts are INSIGNIFICANT, so they don't have to be used.
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document.write( "\"A+=+Pe%5E%28rt%29\"
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document.write( "Doubling means that A = 2P. We then get:
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document.write( "\"2P+=+Pe%5E%28rt%29\"
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document.write( "\"2P%2FP+=+e%5E%28rt%29\"
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document.write( "\"2+=+e%5E%28rt%29\"
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document.write( "\"2+=+e%5E%28.0225t%29\" ------ Substituting .0225 (2.25%) for r
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document.write( "\"ln+%282%29+=+.0225t\" ----- Converting to LOGARITHMIC (natural) form
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document.write( "t, or time = 
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document.write( "Note that 30.80654 is NOT THE SAME as 32 years. Even if it were requested that time be rounded to the nearest year, it'd be 31, not 32. \n" );
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