document.write( "Question 83991: Please show me the way.. A restaurant determined that it's monthly cost function is given by C=3000=16q, where q is the number of dinners sold per month. q=1200-20p, where p is the price of the dinner.
\n" ); document.write( "a) Solve for p in terms of q and write the revenue and profit as a function of q
\n" ); document.write( "b) Find the break even point in terms of q. (the min and max # dinners/mo it can serve without losing $)
\n" ); document.write( "c) Write the cost, revenue and profit as functions of p and find breakeven points in terms of p.
\n" ); document.write( "d) Determin range of prices for which the restaurant make a profit.
\n" ); document.write( "I know this is alot, but I am lost. Any help is appreciated.
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Algebra.Com's Answer #60469 by ankor@dixie-net.com(22740)\"\" \"About 
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A restaurant determined that it's monthly cost function is given by C=3000=16q, where q is the number of dinners sold per month.
\n" ); document.write( "q = 1200-20p, where p is the price of the dinner.
\n" ); document.write( ":
\n" ); document.write( "a) Solve for p in terms of q and write the revenue and profit as a function of q
\n" ); document.write( "q = 1200-20p
\n" ); document.write( "+20p = 1200 - q
\n" ); document.write( "p = \"%28%281200-q%29%29%2F20\"
\n" ); document.write( ":
\n" ); document.write( "Revenue = p * q; substitute \"%28%281200-q%29%29%2F20\" for p:\r
\n" ); document.write( "\n" ); document.write( "Rev = q(\"%28%281200-q%29%29%2F20\")
\n" ); document.write( "
\n" ); document.write( "Rev = \"%28%281200q+-+q%5E2%29%29%2F20\"
\n" ); document.write( "Rev = \"%2860q+-+.05q%5E2%29\"; divide both terms by 20
\n" ); document.write( ":
\n" ); document.write( "Profit = Rev - Cost
\n" ); document.write( ":
\n" ); document.write( "Profit = (60q - .05q^2) - (3000 + 16q)
\n" ); document.write( ":
\n" ); document.write( "Profit = 60q - .05q^2 - 3000 - 16q
\n" ); document.write( ":
\n" ); document.write( "Profit = -.05q^2 + 44q - 3000
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "b) Find the break even point in terms of q. (the min and max # dinners/mo it can serve without losing $)
\n" ); document.write( "Breakeven point is when profit = 0
\n" ); document.write( ":
\n" ); document.write( "-.05q^2 + 44q - 3000 = 0
\n" ); document.write( ":
\n" ); document.write( "Using the quadratic formula, I got:
\n" ); document.write( "q ~ 75 meals min and q ~ 805 max, to not lose money
\n" ); document.write( ":
\n" ); document.write( "Graph this equation:
\n" ); document.write( "\"+graph%28+300%2C+200%2C+-200%2C+1000%2C+-1000%2C+8000%2C+-.05x%5E2+%2B+44x+-+3000%29+\"
\n" ); document.write( "Profit on the vertical and number of meals on the horizontal
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "c) Write the cost, revenue and profit as functions of p and find breakeven points in terms of p.
\n" ); document.write( ":
\n" ); document.write( "Cost = 3000 + 16q
\n" ); document.write( "q = 1200-20p
\n" ); document.write( "Replace q with (1200-20p)
\n" ); document.write( "Cost = 3000 + 16(1200- 20p)
\n" ); document.write( "Cost = 3000 + 19200 - 320p
\n" ); document.write( "Cost = 22200 -320p
\n" ); document.write( ":
\n" ); document.write( "Revenue = p * q
\n" ); document.write( "Replace q with (1200-20p)
\n" ); document.write( "Rev = p(1200-20p)
\n" ); document.write( "Rev = 1200p - 20p^2
\n" ); document.write( ":
\n" ); document.write( "Profit = Revenue - Cost
\n" ); document.write( "Profit = 1200p - 20p^2 - (22200 - 320p)
\n" ); document.write( "Profit = 1200p - 20p^2 - 22200 + 320p
\n" ); document.write( "Profit = -20p^2 + 1520p - 21000
\n" ); document.write( ":
\n" ); document.write( "Breakeven is when profit = 0
\n" ); document.write( "-20p^2+ 1520p - 21000 = 0
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "d) Determine range of prices for which the restaurant make a profit.
\n" ); document.write( ":
\n" ); document.write( "Solve for p in the above equation: I got p = 18.93 and p = 57.85
\n" ); document.write( "Profit between these two values
\n" ); document.write( "Graph would look like this:
\n" ); document.write( "\"+graph%28+300%2C+200%2C+-10%2C+70%2C+-1000%2C+8000%2C+-20x%5E2%2B+1520x+-+21000+%29+\"
\n" ); document.write( "Profit on the vertical and meal price on the horizonal
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "A lot of chance for error here, check my calculations.\r
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