Question

the population proportion is 0.40, what is the probability that a simple proportion will be within +0.03, -0.03 of the population proportion if the sample size in 200?

Answer 1

Solution

Given that,

p = 0.40

1 - p = 0.60

n = 200

= p = 0.40

=  [p ( 1 - p ) / n] = [(0.40 * 0.60) / 200 ] = 0.0346

= P[(-0.03 / 0.0346) / < ( - ) / < (0.03 / 0.0346) / ]

= P(-0.87 < z < 0.87)

= P(z < 0.87) - P(z < -0.87)

= 0.8078 - 0.1922

= 0.6156

Probability = 0.6156