document.write( "Question 1198755: Suppose that the demand equation for a monopolist’s product is P=400-2Q and the average cost function is AC=400/Q+4+0.2Q , where Q is the number of units and p is the price per unit.
\n" ); document.write( " Write down the equations for TC and TR.
\n" ); document.write( "Calculate the price and quantity at which profit is maximised. Determine the maximum profit.
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Algebra.Com's Answer #848286 by CPhill(1959)\"\" \"About 
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**1. Find the Total Cost (TC) Equation**\r
\n" ); document.write( "\n" ); document.write( "* **Total Cost (TC) = Average Cost (AC) * Quantity (Q)**
\n" ); document.write( "* TC = (400/Q + 4 + 0.2Q) * Q
\n" ); document.write( "* TC = 400 + 4Q + 0.2Q²\r
\n" ); document.write( "\n" ); document.write( "**2. Find the Total Revenue (TR) Equation**\r
\n" ); document.write( "\n" ); document.write( "* **Total Revenue (TR) = Price (P) * Quantity (Q)**
\n" ); document.write( "* TR = (400 - 2Q) * Q
\n" ); document.write( "* TR = 400Q - 2Q²\r
\n" ); document.write( "\n" ); document.write( "**3. Find the Profit (π) Equation**\r
\n" ); document.write( "\n" ); document.write( "* **Profit (π) = Total Revenue (TR) - Total Cost (TC)**
\n" ); document.write( "* π = (400Q - 2Q²) - (400 + 4Q + 0.2Q²)
\n" ); document.write( "* π = 400Q - 2Q² - 400 - 4Q - 0.2Q²
\n" ); document.write( "* π = 396Q - 2.2Q² - 400\r
\n" ); document.write( "\n" ); document.write( "**4. Find the Quantity that Maximizes Profit**\r
\n" ); document.write( "\n" ); document.write( "* To find the quantity that maximizes profit, we need to find the derivative of the profit function with respect to Q and set it to zero.
\n" ); document.write( "* dπ/dQ = 396 - 4.4Q = 0
\n" ); document.write( "* 4.4Q = 396
\n" ); document.write( "* Q = 90\r
\n" ); document.write( "\n" ); document.write( "**5. Find the Price at Maximum Profit**\r
\n" ); document.write( "\n" ); document.write( "* Substitute the optimal quantity (Q = 90) into the demand equation:
\n" ); document.write( "* P = 400 - 2 * 90
\n" ); document.write( "* P = 400 - 180
\n" ); document.write( "* P = $220\r
\n" ); document.write( "\n" ); document.write( "**6. Calculate the Maximum Profit**\r
\n" ); document.write( "\n" ); document.write( "* Substitute the optimal quantity (Q = 90) into the profit function:
\n" ); document.write( "* π = 396 * 90 - 2.2 * 90² - 400
\n" ); document.write( "* π = 35640 - 17820 - 400
\n" ); document.write( "* π = $17420\r
\n" ); document.write( "\n" ); document.write( "**Therefore:**\r
\n" ); document.write( "\n" ); document.write( "* **Quantity that maximizes profit:** 90 units
\n" ); document.write( "* **Optimal price:** $220
\n" ); document.write( "* **Maximum profit:** $17,420
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