document.write( "Question 156486: Ted put $4000 in his savings account at Bank A. He put $6,000 in an account at Bank B that paid interest at twice the rate as Bank A. HIs total simple interest for the year was $640. What was the interest rate at each bank? \n" ); document.write( "
Algebra.Com's Answer #115274 by stanbon(75887)\"\" \"About 
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Ted put $4000 in his savings account at Bank A.
\n" ); document.write( "Let interest rate be x ; Interest = 4000x dollars
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\n" ); document.write( "He put $6,000 in an account at Bank B that paid interest at twice the rate as Bank A.
\n" ); document.write( "Interest rate = 2x ; Interest = 6000x dollars
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\n" ); document.write( "HIs total simple interest for the year was $640.
\n" ); document.write( "What was the interest rate at each bank?
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\n" ); document.write( "EQUATION:
\n" ); document.write( "4000x + 6000x = 640
\n" ); document.write( "10000x = 640
\n" ); document.write( "x = 0.064 = 6.4% (Bank A interest rate)
\n" ); document.write( "2x = 0.128 = 12.8% (Bank B interest rate)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.\r
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