document.write( "Question 622654: How can $60,000 be invested, part at 7% annual simple interest and the remainder at 12% annual simple interest, so that the interest earned by the two accounts will be equal? \n" ); document.write( "
Algebra.Com's Answer #391564 by math-vortex(648)\"\" \"About 
You can put this solution on YOUR website!
Hi, there--
\n" ); document.write( ".
\n" ); document.write( "We can use algebra to solve this.
\n" ); document.write( ".
\n" ); document.write( "Let x be the amount of money invested at 7% simple interest.
\n" ); document.write( ".
\n" ); document.write( "The money invested in both accounts sums up to $60,000, so the expression 60000-x represents the amount of money invested at 12% simple interest.
\n" ); document.write( ".
\n" ); document.write( "Now express the interest rates in decimal form: 7% = 0.07 and 12% = 0.12
\n" ); document.write( ".
\n" ); document.write( "The amount of interest earned on the the first account is the interest rate times the amount invested, or 0.07x.
\n" ); document.write( ".
\n" ); document.write( "Likewise, the amount of interest earned on the second account is its interest rate times the amount invested, or 0.12*(60000-x).
\n" ); document.write( ".
\n" ); document.write( "We want the interest earned on the two accounts to be equal, so we write an equation showing the two expressions to be equal.
\n" ); document.write( ".
\n" ); document.write( "[interest earned at 7%] = [interest earned at 12%]
\n" ); document.write( ".
\n" ); document.write( "\"0.7x=0.12%2860000-x%29\"
\n" ); document.write( ".
\n" ); document.write( "Now simplify and solve for x.
\n" ); document.write( ".
\n" ); document.write( "\"0.7x=7200-0.12x\"
\n" ); document.write( ".
\n" ); document.write( "Add 0.12x to both sides of the equation.
\n" ); document.write( ".
\n" ); document.write( "\"0.7x%2B0.12x=7200\"
\n" ); document.write( "\"0.19x=7200\"
\n" ); document.write( ".
\n" ); document.write( "Divide both sides of the equation by 0.19.
\n" ); document.write( ".
\n" ); document.write( "\"x=7200%2F0.19\"
\n" ); document.write( "\"x=37894.74\"
\n" ); document.write( ".
\n" ); document.write( "In the context of our problem x=37894.74 means that $37,894.74 should be invested in the account with 7% interest.
\n" ); document.write( ".
\n" ); document.write( "The remainder should be invested in the account with 12% interest. Since 60,000-37,894.74= 22,105.26, we should invest $22,105.26 in the second account.
\n" ); document.write( ".
\n" ); document.write( "The final step is to check that this allocation of the money actually earns the same amount of interest.
\n" ); document.write( ".
\n" ); document.write( "$37,894.74 at 7% interest earns $2,652.63 since 0.07*37894.74=2652.63
\n" ); document.write( "$22,105.26 invested at 12% interest earns $2,652.63 since 0.12*22105.26=2652.63
\n" ); document.write( ".
\n" ); document.write( "That's it. Feel free to email if you have questions about any part of this explanation.
\n" ); document.write( ".
\n" ); document.write( "Ms.Figgy
\n" ); document.write( "math.in.the.vortex@gmail.com
\n" ); document.write( "
\n" );