document.write( "Question 167256: HI,
\n" ); document.write( "It's been decades since I last worked in serious algebra but have hit a mathematical problem that I cannot solve. Your help would be tremendously appreciated.\r
\n" ); document.write( "\n" ); document.write( "Starting Amount = 3,000,000 (- variable c)
\n" ); document.write( "Ending Amount = 0
\n" ); document.write( "Number of Years to withdrawl amounts = 10 (- variable y)
\n" ); document.write( "Withdrawl Amounts increase annually by 3% [inflation rate] (- variable f)
\n" ); document.write( "Each years remaining amount (- variable r) increases by 3.75% [interest rate] (- variable i) = interest (- variable z)
\n" ); document.write( "Each annual withdrawal amount so far is unknown. (- variable x)
\n" ); document.write( "Solve for the initial [first year] withdrawal amount (x).
\n" ); document.write( "Provide a formula to calculate the first x with theb given values above.\r
\n" ); document.write( "\n" ); document.write( "Known Formulas I have figured out that do work with these values:
\n" ); document.write( "Note c = 0.00 in year \"last+y+%2B+1\"\r
\n" ); document.write( "\n" ); document.write( "\"c+-+x+=+r\"
\n" ); document.write( "\"r+%2A+i+=+y\"
\n" ); document.write( "\"r+%2B+z+=+next+c\"
\n" ); document.write( "\"+next+x+=+x+%2B+%28x+%2A+f%29\"
\n" ); document.write( "\"c+=+%28next+c+%2B+x+%2B+%28i+%2A+x%29%29%2F%281+%2B+i%29\"
\n" ); document.write( "\"+last+x+=+first+x+%2A+%281+%2B+f%29%5E%28y+-+1%29\"
\n" ); document.write( "\"+last+c+in+year+10+=+last+x+in+year+10+\"
\n" ); document.write( "\"+last+r+=+0+\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "A sample table with accurate figures doing the same mathematical calculations as needed above but for 3 years instead of 10 is shown below. For this data, all other constants from above remain unchanged. \r
\n" ); document.write( "\n" ); document.write( "y____Funds (c)___Withdrawal(x)__Balance (r)____interest(z)
\n" ); document.write( "1__3,000,000.00__1,007,263.88__1,992,736.12__74,727.60
\n" ); document.write( "2__2,067,463.72__1,037,482.80__1,029,981.93__38,624.32
\n" ); document.write( "3__1,068,606.25__1,068,606.25_____0.00)_______(0.00)
\n" ); document.write( "4_____(0.00)\r
\n" ); document.write( "\n" ); document.write( "As you can see, I have the figures. What I need is the formula so that I can do this in excel.\r
\n" ); document.write( "\n" ); document.write( "Again, many thanks for your help if your able.
\n" ); document.write( "Rick
\n" ); document.write( "

Algebra.Com's Answer #123281 by oscargut(2103)\"\" \"About 
You can put this solution on YOUR website!
Hi, it is a nice problem, i solved.
\n" ); document.write( "If you want more details please contact me
\n" ); document.write( "( solution is too long to put it here)
\n" ); document.write( "If you want i can do excel file too
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