document.write( "Question 905835: Mark invested $12,500, part at 5% and part at 7% simple interest for a period of 1 yr. How much was invested in each account if the interest earned in the 7% account was $440 greater than the interest earned in the 5% account? \n" ); document.write( "
Algebra.Com's Answer #549550 by richwmiller(17219)\"\" \"About 
You can put this solution on YOUR website!
We know the total amount of money invested. $12500
\n" ); document.write( "x+y=12500,
\n" ); document.write( "We know that the difference in interest earned by the two accounts is $440
\n" ); document.write( "0.07*x-0.05*y=440
\n" ); document.write( "x=12500-y
\n" ); document.write( "We substitute for x
\n" ); document.write( "0.07*(12500-y)-0.05*y=440
\n" ); document.write( "We multiply out
\n" ); document.write( "875-0.07y-0.05*y=440
\n" ); document.write( "We combine like terms.
\n" ); document.write( "435=0.12*y
\n" ); document.write( "Isolate y
\n" ); document.write( "y=435/0.12
\n" ); document.write( "y=3625 at 5%
\n" ); document.write( "Calculate x
\n" ); document.write( "x=12500-3625
\n" ); document.write( "x=8875 at 7%
\n" ); document.write( "Interest earned at 7% is 621.25
\n" ); document.write( "Interest earned at 5% is 181.25
\n" ); document.write( "We check
\n" ); document.write( "0.07*8875-0.05*3625=440
\n" ); document.write( "621.25-181.25=440
\n" ); document.write( "440=440
\n" ); document.write( "Since this statement is TRUE and neither amount is negative then all is well\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "
\n" );