Question

​n=150

N10000

p=.4

(b) What is the probability of obtaining x=63 or more individuals with the​ characteristic? That​ is, what is ​P(^p greater or equal to 0.42​)?

(c) What is the probability of obtaining x=54 or fewer individuals with the​ characteristic? That​ is, what is ​P(^p less than or equal to 0.36)?

Answer 1

n = 150

N = 10,000

p = 0.4

N/n = 10,000/150 = 66.67 > 10

Distribution of sample proportion can be assumed normal: P( < A) = P(Z < (A - )/)

= p = 0.4

=

=

= 0.04

(b) P( 0.42) = 1 - P( < 0.42)

= 1 - P(Z < (0.42 - 0.4)/0.04)

= 1 - P(Z < 0.5)

= 1 - 0.6915

= 0.3085

(c) P( 0.36) = P(Z < (0.36 - 0.4)/0.04)

= P(Z < -1)

= 0.1587