document.write( "Question 1039400: you borrow $1400 from a friend and promise to pay back $2000 in two years. What simple interest rate, to the nearest tenth of a percent, will you pay? \n" ); document.write( "
Algebra.Com's Answer #654132 by Theo(13342)\"\" \"About 
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simple interest formula is i = p * r * n
\n" ); document.write( "i is the interest.
\n" ); document.write( "p is the principal
\n" ); document.write( "r is the interest rate per time period
\n" ); document.write( "n is the number of time periods.\r
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\n" ); document.write( "\n" ); document.write( "the time period is in years.
\n" ); document.write( "the interest rate will therefore be per year.\r
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\n" ); document.write( "\n" ); document.write( "i is equal to the amount you payed minus the amount that you owed.
\n" ); document.write( "that becomes 2000 - 1400 = 600\r
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\n" ); document.write( "\n" ); document.write( "i = 600
\n" ); document.write( "n = 2 years
\n" ); document.write( "p = 1400, which is the amount that you borrowed.\r
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\n" ); document.write( "\n" ); document.write( "the formula becomes 600 = 1400 * r * 2
\n" ); document.write( "simplify to get 600 = 2800 * r
\n" ); document.write( "divide both sides of the equation by 2800 to get:
\n" ); document.write( "600 / 2800 = r
\n" ); document.write( "solve for r to get r = 600/2800 = 6/28 = 3/14 = .21485714.
\n" ); document.write( "multiply that by 100 to get 21.485714%.
\n" ); document.write( "round to 1 decimal place to get 21.5%.\r
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\n" ); document.write( "\n" ); document.write( "you are paying simple interest rate of 21.5% per year.
\n" ); document.write( ".215 * 1400 = 301.
\n" ); document.write( "multiply that by 2 to get 602.
\n" ); document.write( "without rounding, it would have been 600.\r
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