document.write( "Question 365128: Please help me solve this word problem: at an interest rate of 8%, compounded annually, how long will it take to double an investment of $100? of 500? of 1200? I'm pretty sure that I have to use the equation A=P(1+r/n)^(nt). I need help setting it up. Would I fill in the equation like this:A=100(1+.08/x)^2? \n" ); document.write( "

Algebra.Com's Answer #260357 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!


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document.write( "Hi, 
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document.write( "*Note: 
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document.write( " A=P(1+r/n)^(nt). 
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document.write( "A = amount of money accumulated after n years, including interest.
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document.write( "P = principal amount (the initial amount you borrow or deposit) 
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document.write( "r  = annual rate of interest (as a decimal)
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document.write( "t  = number of years the amount is deposited or borrowed for.
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document.write( "n  =  number of times the interest is compounded per year
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document.write( "In this example, n is 1 as the interest compounds annually
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document.write( "interest rate of 8%, how long will it take to double an investment of $100 
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document.write( "200=100*(1+.08)^t
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document.write( "2 = 1.08 ^t
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document.write( "2 = 1.08^9
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document.write( "t = 9 yrs to double your money (for each amount of investment given)\r
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