document.write( "Question 1128087: An investment of $106,000 was made by a business club. The investment was split into three parts and lasted for one year. The first part of the investment earned 8% interest, the second 6%, and the third 9%. Total interest from the investments was $8100. The interest from the first investment was 4 times the interest from the second. Find the amounts of the three parts of the investment. \n" ); document.write( "
Algebra.Com's Answer #839202 by mananth(16946)![]() ![]() You can put this solution on YOUR website! An investment of $106,000 was made by a business club.\r \n" ); document.write( "\n" ); document.write( " The investment was split into three parts and lasted for one year.\r \n" ); document.write( "\n" ); document.write( " The first part of the investment earned 8% interest, Let investment be x\r \n" ); document.write( "\n" ); document.write( " the second 6%, let investment be y\r \n" ); document.write( "\n" ); document.write( " and the third 9%. let investment be z\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "x+y+z =106000----------------------------------------(1)\r \n" ); document.write( "\n" ); document.write( " Total interest from the investments was $8100. \n" ); document.write( "8%x+6%y+9%z = 8100 -------------------------------(2)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "The interest from the first investment was 4 times the interest from the second. \n" ); document.write( "8%x= 4*6%y \n" ); document.write( "8x=24y \n" ); document.write( "x=3y \n" ); document.write( "substitute x=3y in (1) \n" ); document.write( "x+y+z=106000 \n" ); document.write( "4y+z=106000 ----------------------------(3)\r \n" ); document.write( "\n" ); document.write( "8%x+6%y+9%z = 8100 \n" ); document.write( "substitute x=3y\r \n" ); document.write( "\n" ); document.write( "8%(3y)+6%y+9%z=8100 \n" ); document.write( "Multiply by 100 \n" ); document.write( "24y +6y +9z= 810000 \n" ); document.write( "30y+9z= 810000 --------------------------(4) \n" ); document.write( "multiply (3)by 9 and subtract (4)\r \n" ); document.write( "\n" ); document.write( "36y+9z=954000 \n" ); document.write( "30y+9z= 810000\r \n" ); document.write( "\n" ); document.write( "6y= 144000 \n" ); document.write( "y= 24000\r \n" ); document.write( "\n" ); document.write( "x=3y \n" ); document.write( "x= 72000\r \n" ); document.write( "\n" ); document.write( "106000 -96000 = 10000 =z\r \n" ); document.write( "\n" ); document.write( "The first part of the investment earned 8% interest. $72,000\r \n" ); document.write( "\n" ); document.write( " the second 6%, investment . $24,000\r \n" ); document.write( "\n" ); document.write( " and the third 9%. investment $ 10,000\r \n" ); document.write( "\n" ); document.write( "Check\r \n" ); document.write( "\n" ); document.write( "72000*8%+24000*6%+9%*10000 =8100\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |