document.write( "Question 1173770: A major city wants to establish a sinking fund to pay off debts of PKR 800 million which come due in 10 years. The city can earn interest at the rate of 8 percent per year compounded monthly. If first deposit is made 1 month from now;
\n" ); document.write( "a)What monthly deposit will be required to accumulate the PKR 800 million?
\n" ); document.write( "b)How much interest will be earned on these deposits
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Algebra.Com's Answer #850718 by CPhill(1959)\"\" \"About 
You can put this solution on YOUR website!
Here's how to calculate the required monthly deposit and the total interest earned:\r
\n" ); document.write( "\n" ); document.write( "**a) Monthly Deposit**\r
\n" ); document.write( "\n" ); document.write( "* **Future Value (FV):** PKR 800,000,000
\n" ); document.write( "* **Annual Interest Rate (r):** 8% or 0.08
\n" ); document.write( "* **Number of Years (t):** 10
\n" ); document.write( "* **Compounding Periods per Year (n):** 12 (monthly)\r
\n" ); document.write( "\n" ); document.write( "1. **Calculate the Monthly Interest Rate (i):**
\n" ); document.write( " * i = r / n = 0.08 / 12 ≈ 0.006667\r
\n" ); document.write( "\n" ); document.write( "2. **Calculate the Total Number of Periods (nt):**
\n" ); document.write( " * nt = n * t = 12 * 10 = 120\r
\n" ); document.write( "\n" ); document.write( "3. **Use the Sinking Fund Formula:**
\n" ); document.write( " * PMT = FV * [i / ((1 + i)^nt - 1)]
\n" ); document.write( " * PMT = 800,000,000 * [0.006667 / ((1 + 0.006667)^120 - 1)]
\n" ); document.write( " * PMT ≈ 800,000,000 * [0.006667 / (2.219416 - 1)]
\n" ); document.write( " * PMT ≈ 800,000,000 * [0.006667 / 1.219416]
\n" ); document.write( " * PMT ≈ 800,000,000 * 0.005467
\n" ); document.write( " * PMT ≈ 4,373,600 PKR\r
\n" ); document.write( "\n" ); document.write( "Therefore, the city needs to deposit approximately **PKR 4,373,600** each month.\r
\n" ); document.write( "\n" ); document.write( "**b) Total Interest Earned**\r
\n" ); document.write( "\n" ); document.write( "1. **Calculate the Total Amount Deposited:**
\n" ); document.write( " * Total Deposited = Monthly Deposit * Number of Payments
\n" ); document.write( " * Total Deposited = 4,373,600 * 120 = 524,832,000 PKR\r
\n" ); document.write( "\n" ); document.write( "2. **Calculate the Total Interest Earned:**
\n" ); document.write( " * Total Interest = Future Value - Total Deposited
\n" ); document.write( " * Total Interest = 800,000,000 - 524,832,000 = 275,168,000 PKR\r
\n" ); document.write( "\n" ); document.write( "Therefore, the total interest earned will be approximately **PKR 275,168,000**.\r
\n" ); document.write( "\n" ); document.write( "**Using the provided code result to verify**\r
\n" ); document.write( "\n" ); document.write( "The code provided the results.
\n" ); document.write( "Monthly deposit required: PKR 4372874.22
\n" ); document.write( "Total interest earned: PKR 275255094.19\r
\n" ); document.write( "\n" ); document.write( "The answers are very close to the manually calculated answers. The small difference is due to rounding during the manual calculation.
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