document.write( "Question 1006877: The formula A=P(1+r)^2 gives the amount A in dollars that P dollars will grow to in 2 years at interest rate r (where r is given as a decimal), using compound interest. What interest rate will cause $1000 to grow to $1092.03 in 2 years? Round your answer to the nearest tenth of a percent if needed. \n" ); document.write( "
Algebra.Com's Answer #622922 by Theo(13342)\"\" \"About 
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the formula is A = P * (1+r)^2\r
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\n" ); document.write( "\n" ); document.write( "P = 1000
\n" ); document.write( "r = the annual interest rate
\n" ); document.write( "A = 1092.03\r
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\n" ); document.write( "\n" ); document.write( "the formula becomes:\r
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\n" ); document.write( "\n" ); document.write( "1092.03 = 1000 * (1+r)^2\r
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\n" ); document.write( "\n" ); document.write( "divide both sides of this equation by 1000 to get:\r
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\n" ); document.write( "\n" ); document.write( "1092.03 / 1000 = (1+r)^2\r
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\n" ); document.write( "\n" ); document.write( "raise both sides of that equation to the power of 1/2 to get:\r
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\n" ); document.write( "\n" ); document.write( "(1092.03 / 1000) ^ (1/2) = 1 + r\r
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\n" ); document.write( "\n" ); document.write( "the expression on the right side of the equation becomes 1 + r because:\r
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\n" ); document.write( "\n" ); document.write( "((1+r)^2)^(1/2) becomes (1+r)^(2 * 1/2) which becomes (1+r)^1 which becomes 1+r.\r
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\n" ); document.write( "\n" ); document.write( "subtract 1 from both sides of this equation to get:\r
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\n" ); document.write( "\n" ); document.write( "(1092.03 / 1000) ^ (1/2) - 1 = r\r
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\n" ); document.write( "\n" ); document.write( "solve for r to get:\r
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\n" ); document.write( "\n" ); document.write( "r = .045002392\r
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\n" ); document.write( "\n" ); document.write( "confirm by replacing r in the original equation with .045002392 to get:\r
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\n" ); document.write( "\n" ); document.write( "1092.03 = 1000 * (1.045002392)^2 which becomes:\r
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\n" ); document.write( "\n" ); document.write( "1092.03 = 1092.03, confirming the solution is correct.\r
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\n" ); document.write( "\n" ); document.write( "your solution is r = .045002392\r
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\n" ); document.write( "\n" ); document.write( "the percent is 100 * .045002392 = 4.5002392%.\r
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\n" ); document.write( "\n" ); document.write( "round that to the nearest tenth of a percent and your solution becomes:\r
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\n" ); document.write( "\n" ); document.write( "r = 4.5%.\r
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