document.write( "Question 1166068: Margo borrows $1200, agreeing to pay it back with 7% annual interest after 10 months. How much interest will she pay? \n" ); document.write( "
Algebra.Com's Answer #790547 by Theo(13342)\"\" \"About 
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7% annual interest means the interest rate is compound yearly.
\n" ); document.write( "the formula for interest rate being compounded yearly is:
\n" ); document.write( "f = p * (1 + r) ^ n
\n" ); document.write( "f is the future value
\n" ); document.write( "p is the present value
\n" ); document.write( "r is the interest rate per year.
\n" ); document.write( "n is the number of years.\r
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\n" ); document.write( "\n" ); document.write( "since 10 months = 10/12 of a year, then the formula becomes:
\n" ); document.write( "f = 1200 * (1 + .07) ^ (10/12)
\n" ); document.write( "this results in f = 1200 * 1.07 ^ (10/12)
\n" ); document.write( "this results in f = 1269.602379
\n" ); document.write( "since i = f - p, then i = 69.602379
\n" ); document.write( "in this formula, i represents the interest, f represents the future value, p represents the present value.\r
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