Suppose a candidate for public office is favored by only 48% of the voters. if a sample survey randomly selects 2500 voters, the
percentage in the sample who favor the candidate can be thought of as a measurement from a normal curve with a mean of 48% and a standard deviation of 1%. based on this information, how often would such a survey show that 50% or more of the sample favored the candidate?
Mean=0.48 standard deviation=0.01 thus using the z-score: P(x>0.5) we shall have the following: z=(0.5-0.48)/0.01=2 thus P(x>0.5) =1-P(x<0.5) =1-P(z<2) =1-0.9772 =0.0228
