Statistics
posted by Tom .
Determine the sample size necessary to estimate a population proportion to within .03 with 90% confidence assuming you have no knowledge of the approximate value of the sample proportion.

Try this formula:
n = [(zvalue)^2 * p * q]/E^2
Note: n = sample size needed; .5 for p and .5 for q are used if no value is stated in the problem. E = maximum error, which is .03 in the problem. Zvalue is found using a ztable to represent 90% interval. Round final result to next highest whole number.
Also: ^2 means squared and * means to multiply.
I hope this will help get you started. 
n = [(zvalue)^2 * p * q]/E^2
Respond to this Question
Similar Questions

statistics
Determine the sample size required to estimate a population proportion to within 0.032 with 95.7% confidence, assuming that you have no knowledge of the approximate value of the sample proportion. Sample Size = B. Repeat part the previous … 
Statistics
Find the minimum sample size that should be chosen to assure that the proportion estimate p will be within the required margin of error, .06. Use a 95% confidence interval and a population proportion of .7. The critical value for a … 
Stats
2) Find the minimum sample size that should be chosen to assure that the proportion estimate p will be within the required margin of error, .06. Use a 95% confidence interval and a population proportion of .7. The critical value for … 
statistics  please help
A researcher wishes to be 95% confident that her estimate of the population proportion of individuals who travel overseas is within 4% of the true proportion. Find the sample size necessary. In a prior study, a sample of 200 people … 
Elementary Statistics
1) Construct a confidence interval of the population proportion at the given level of confidence. x=60,n=300, 99% confidence. The 99% confidence interval is (_,_) 2) A researcher wishes to estimate the proportion of adults who have … 
Statistics
Suppose the U.S. president wants an estimate of the proportion of the population who support his current policy toward revisions in the Social Security system. The president wants the estimate to be within 0.028 of the true proportion. … 
Statistics Math
The sample proportion is never equal to the population proportion We expect 95% confidence intervals to contain the sample proportion 95% of the time Are the above statements true? 
Statistics
In a prior sample of U.S. adults, the Center for Disease Control (CDC), found that 10% of the people in this sample had pinworm but the margin of error for the population estimate was too large. They want an estimate that is in error … 
Data Analysis
A) An insurance company wants to estimate the proportion of people unsatisfied with their new telephone help service. A survey of 200 callers revealed 45 were unsatisfied with the service. Construct by hand a 95% confidence interval … 
Math (Statistics)
The Centers for Disease Control reported the percentage of people 18 years of age and older who smoke (CDC website, December 14, 2014). Suppose that a study designed to collect new data on smokers and nonsmokers uses a preliminary …