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| Question 1120131:  #8
 A political candidate has asked you to conduct a poll to determine what percentage of people support her.
 If the candidate only wants a 6% margin of error at a 90% confidence level, what size of sample is needed?
 Give your answer in whole people.
 
 Answer by rothauserc(4718)
      (Show Source): 
You can put this solution on YOUR website! there is not enough information to solve this problem without making certain assumptions :
 if you were given the standard deviation of the population, it is solvable
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 assume the population is large, say 100,000 and the proportion is 50% of the population supports the candidate
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 then the formula for sample sizing using the proportion formula yields an answer of 188
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 note that the sample size does not increase appreciably with populations greater than 100,000
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