Posted by Tom on Tuesday, July 30, 2013 at 1:52pm.
In a poll of 700 selected people in the USA who are 50 years or older, 20% said they would prefer a complete overhauling of the social security system. Estimate the population proportion of the USA of 50 years or older who would prefer a complete overhauling of the social security system. Use a 95% confidence level. What is the minimum number of people required that would give a sampling error of only 5%?

statistics  MathGuru, Tuesday, July 30, 2013 at 6:58pm
Try this formula:
n = [(zvalue)^2 * p * q]/E^2
= [(1.96)^2 * .2 * .8]/.05^2
I'll let you finish the calculation.
Note: n = sample size needed; .2 (20%)for p and .8 (which is 1  p) for q. E = maximum error, which is .05 (5%) in the problem. Zvalue is found using a ztable (for 95%, the value is 1.96). Symbols: * means to multiply and ^2 means squared.
I hope this will help get you started.
Answer This Question
Related Questions
 statistics  The 2003 Statistical Abstract of the United States reported the ...
 Statistics (46)  The 2003 Statistical Abstract of the United States reported ...
 statistics  Sweden is reported to have among the highest percentage of citizens...
 Statistics  Suppose the U.S. president wants an estimate of the proportion of ...
 social studies  Does anyone know a place where I can find out what the required...
 Economics (45)  The 2003 Statistical Abstract of the United States reported the...
 English  1. I can't wait to go to the USA. 2. I look forward to going to the ...
 college algebra  In the state of Indiana, 192,031 people claim not to speak ...
 damonsteve help statistics  Statistics City XYZ has 8800 registered voters. ...
 MTH233/statistics UOP  You work for the public relations department of the ...
More Related Questions