document.write( "Question 73166: I have been trying to figure out the word problem below for a while and can't understand what numbers to plug into the function to solve.\r
\n" ); document.write( "\n" ); document.write( "Exponential growth rate for a product is 10% per year. Using the exponential growth function(N=N0e^rt) with r as growth rate, t as number of years since 1995 and N0 as demand in 1995, when will the demand be double that of 1995? \n" ); document.write( "
Algebra.Com's Answer #52428 by ankor@dixie-net.com(22740)\"\" \"About 
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Exponential growth rate for a product is 10% per year. Using the exponential growth function(N=N0e^rt) with r as growth rate, t as number of years since 1995 and N0 as demand in 1995, when will the demand be double that of 1995?
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\n" ); document.write( "Let the demand (No) = k, then double the demand (N)= 2k, r = .1 (decimal of 10%)
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\n" ); document.write( "No(e^rt) = N
\n" ); document.write( "k(e^.1t) = 2k; find t
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\n" ); document.write( "Divide both sides by k:
\n" ); document.write( "e^.1t = 2
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\n" ); document.write( "Find the natural log of both sides: remember the nat log of e is 1, so we have:
\n" ); document.write( ".1t = ln(2)
\n" ); document.write( ".1t = .693147
\n" ); document.write( "t = .693147/.1
\n" ); document.write( "t = 6.93 years, call it 7 years (2002)
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\n" ); document.write( "Check our solution using No = 10
\n" ); document.write( "10(e^(.1*7)=
\n" ); document.write( "10(e^.7) =
\n" ); document.write( "10(2.01) = 20 = N
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\n" ); document.write( "Did this make sense to you?\r
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