A research firm conducted a survey to determine the mean amount (in pesos) heavy smokers spends on cigarettes in a week. A sample of 36 heavy smokers revealed that sample mean is 1000 with the standard deviation of 200. What would be a 95% margin of error for your estimate?
In a December 2016 survey by Pulse Asia, 85% of the 1450 adults disagreed with the view that martial law is needed to resolve the various problems currently facing the country. Use this information to give a point estimate and a 95% margin of error for the true proportion of all Filipinos who believe martial law is not needed to solve national problems.