Question

Question

A survey of 1000 people answering yes and no is taken. If the population proportion of "yes’’ answers is assumed to be 0.60, what is the probability that 62% or more in the survey will answer yes? (Use the normal approximation to give an answer).

Answer 1

p = 0.60

n = 1000

P( < A) = P(Z < (A - )/)

= p = 0.60

=

=

= 0.0155

P(62% or more in the survey will answer yes) = P( > 0.62)

= 1 - P( < 0.62)

= 1 - P(Z < (0.62 - 0.60)/0.0155)

= 1 - P(Z < 1.29)

= 1 - 0.9015

= 0.0985