document.write( "Question 122541: I stuck on this problem and have been for a while. I hope you can help me out!!\r
\n" ); document.write( "\n" ); document.write( "A quiz program gives a prize of $5 for teh first question answered correctly. The contestant's prize winnings are doubled for each question after the first. How many questions would you need to answer to exceed $1,000,000 in total prize money?\r
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Algebra.Com's Answer #89960 by Fombitz(32388)\"\" \"About 
You can put this solution on YOUR website!
This looks like exponential growth.
\n" ); document.write( "The formula for exponential growth is
\n" ); document.write( "\"f%28t%29=k%2Ae%5E%28%28alpha%29+t%29\"
\n" ); document.write( "We just need to determine \"k\" and \"alpha\"
\n" ); document.write( "\"f%281%29=k%2Ae%5E%28%28alpha%29%29=5\"
\n" ); document.write( "\"f%282%29=k%2Ae%5E%282%28alpha%29%29=10\"
\n" ); document.write( "\"e%5E%282%28alpha%29%29%2Fe%5E%28alpha%29=10%2F5\"
\n" ); document.write( "\"e%5E%28alpha%29=2\"
\n" ); document.write( "\"%28alpha%29=ln%282%29\"
\n" ); document.write( "\"%28alpha%29=0.693\"\r
\n" ); document.write( "\n" ); document.write( "\"f%281%29=k%2Ae%5E%28%28alpha%29%29=5\"
\n" ); document.write( "\"k%2Ae%5E%280.693%29=5\"
\n" ); document.write( "\"2k=5\"
\n" ); document.write( "\"k=2.5\"
\n" ); document.write( "\"f%28t%29=2.5%2Ae%5E%280.693t%29\"
\n" ); document.write( "So, what is t so that f(t)>1000000
\n" ); document.write( "\"2.5%2Ae%5E%280.693t%29%3E1000000\"
\n" ); document.write( "\"e%5E%280.693t%29%3E400000\"
\n" ); document.write( "\"0.693t%3Eln%28400000%29\"
\n" ); document.write( "\"0.693t%3E12.89922\"
\n" ); document.write( "\"t%3E18.61\"
\n" ); document.write( "The first time would be the 19th correct question.
\n" ); document.write( "For 19 correct answers, you would win
\n" ); document.write( "\"f%2819%29=2.5%2Ae%5E%280.693%2819%29%29\"
\n" ); document.write( "\"f%2819%29=2.5%2Ae%5E%2813.167%29\"
\n" ); document.write( "\"f%2819%29=1307059.78\"
\n" ); document.write( "The payout would be $1.307,059.78.
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