SOLUTION: A contestant on a quiz show wins $100 for answering the first question correctly, $200 for answering the second question correctly, and so on, winning twice as much for each CORREC

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Question 1041397: A contestant on a quiz show wins $100 for answering the first question correctly, $200 for answering the second question correctly, and so on, winning twice as much for each CORRECT answer as for the previous CORRECT answer. Alvin answered eight consecutive questions correctly. What is the number of dollars he won?
Answer: $25,500 (How?)
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
It's a geometric series with a starting value of 100, common ratio of 2, and 8 terms.
S%5Bn%5D=%28a%5B1%5D%281-r%5En%29%29%2F%281-r%29
S%5B8%5D=%28100%281-2%5E8%29%29%2F%281-2%29
S%5B8%5D=%28100%281-256%29%29%2F%28-1%29
S%5B8%5D=-100%28-255%29
S%5B8%5D=25500