document.write( "Question 1205323: Siti has RM450000 in her ASB. She wants to invest in Gading Mutual deposit, Maju
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document.write( "Makmur bar gold, Indah certificate deposit and Selamat Maju bar gold which pay
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document.write( "simple annual interest of 9%, 6%, 10% and 15%, respectively. Moreover, she wants
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document.write( "to combine annual return of 8% and want to have only one-third of investment in
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document.write( "Indah certificate deposit and Selamat Maju bar gold.
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document.write( "a. Write the linear model system equation for the whole investment.
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document.write( "c. Use elimination method to find each of the investment \n" );
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Algebra.Com's Answer #847957 by CPhill(1987) You can put this solution on YOUR website! ## Setting up the Linear Model\r \n" ); document.write( "\n" ); document.write( "**Let's denote:** \n" ); document.write( "* **G:** Amount invested in Gading Mutual Deposit \n" ); document.write( "* **M:** Amount invested in Maju Makmur Bar Gold \n" ); document.write( "* **I:** Amount invested in Indah Certificate Deposit \n" ); document.write( "* **S:** Amount invested in Selamat Maju Bar Gold\r \n" ); document.write( "\n" ); document.write( "**Based on the given information, we can set up the following system of linear equations:**\r \n" ); document.write( "\n" ); document.write( "1. **Total Investment:** G + M + I + S = 450000 \n" ); document.write( "2. **Total Annual Return:** 0.09G + 0.06M + 0.10I + 0.15S = 0.08 * 450000 \n" ); document.write( "3. **Indah and Selamat Maju Investment:** I + S = (1/3) * 450000\r \n" ); document.write( "\n" ); document.write( "## Solving the System Using Elimination Method\r \n" ); document.write( "\n" ); document.write( "**Step 1: Simplify the Equations** \n" ); document.write( "* Equation 2: 9G + 6M + 10I + 15S = 360000 \n" ); document.write( "* Equation 3: I + S = 150000\r \n" ); document.write( "\n" ); document.write( "**Step 2: Eliminate a Variable** \n" ); document.write( "* Let's eliminate S. From Equation 3, we can express S as: \n" ); document.write( " * S = 150000 - I \n" ); document.write( "* Substitute S in Equations 1 and 2: \n" ); document.write( " * Equation 1: G + M + I + (150000 - I) = 450000 \n" ); document.write( " => G + M + 150000 = 450000 \n" ); document.write( " * Equation 2: 9G + 6M + 10I + 15(150000 - I) = 360000 \n" ); document.write( " => 9G + 6M - 5I = -750000\r \n" ); document.write( "\n" ); document.write( "**Step 3: Simplify the Equations Further** \n" ); document.write( "* Equation 1: G + M = 300000 \n" ); document.write( "* Equation 2: 9G + 6M - 5I = -750000\r \n" ); document.write( "\n" ); document.write( "**Step 4: Eliminate Another Variable** \n" ); document.write( "* Let's eliminate M. Multiply Equation 1 by -6 and add it to Equation 2: \n" ); document.write( " * -6G - 6M = -1800000 \n" ); document.write( " * 9G + 6M - 5I = -750000 \n" ); document.write( " * ------------------------- \n" ); document.write( " * 3G - 5I = -2550000\r \n" ); document.write( "\n" ); document.write( "**Step 5: Solve for G and I** \n" ); document.write( "* From Equation 1, we can express M as: \n" ); document.write( " * M = 300000 - G \n" ); document.write( "* Substitute M in the simplified Equation 2: \n" ); document.write( " * 3G - 5I = -2550000 \n" ); document.write( " * 3G - 5(150000 - G) = -2550000 \n" ); document.write( " * 8G = 1200000 \n" ); document.write( " * G = 150000 \n" ); document.write( "* Substitute G in M = 300000 - G: \n" ); document.write( " * M = 300000 - 150000 = 150000 \n" ); document.write( "* Substitute G in I + S = 150000: \n" ); document.write( " * I + S = 150000 \n" ); document.write( " * I + (150000 - I) = 150000 \n" ); document.write( " * S = 0\r \n" ); document.write( "\n" ); document.write( "Therefore, the investments are: \n" ); document.write( "* Gading Mutual Deposit: RM150,000 \n" ); document.write( "* Maju Makmur Bar Gold: RM150,000 \n" ); document.write( "* Indah Certificate Deposit: RM150,000 \n" ); document.write( "* Selamat Maju Bar Gold: RM0 \n" ); document.write( " \n" ); document.write( " |