Question

Suppose 60% of the registered voters in a country are Democrats. If a sample of 793 voters is selected, what is the probability that the sample proportion of Democrats will be greater than 64%? Round your answer to four decimal places.

Answer 1

Solution

=  [p( 1 - p ) / n] = [(0.60 * 0.40) / 793 ] = 0.0174

P( > 0.64) = 1 - P( < 0.64)

= 1 - P(( - ) / < (0.64 - 0.60) / 0.0174)

= 1 - P(z < 2.30)

= 1 - 0.9893

= 0.0107