document.write( "Question 390755: hello I just have a question I have been struggling with and was wonderinf if somebody could please help me with it. The question is\r
\n" ); document.write( "\n" ); document.write( "determine the time it takes to double an investment in an account that pays an interest of 4% per annum, compounded quarterly.\r
\n" ); document.write( "\n" ); document.write( "Thankyou so much! \n" ); document.write( "
Algebra.Com's Answer #277103 by stanbon(75887)\"\" \"About 
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determine the time it takes to double an investment in an account that pays an interest of 4% per annum, compounded quarterly.
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\n" ); document.write( "Let's say you invest \"x\" dollars at 4%.
\n" ); document.write( "Doubling will give you \"2x\" dollars.
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\n" ); document.write( "Formula:
\n" ); document.write( "2x = x(1+(0.04/4))^(4t) where t is the number of years.
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\n" ); document.write( "2 = (1+0.01)^4t
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\n" ); document.write( "Take the log of both sides and solve for \"t\":
\n" ); document.write( "4t*log(1.01) = log2
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\n" ); document.write( "4t = log(2)/log(1.01)
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\n" ); document.write( "4t = 69.66
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\n" ); document.write( "t = 17.42 years
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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