In: Statistics and Probability
(a) Based on the information given, is the sample proportion p̂ of residents who have visited the park in the last month approximately normally distributed? Check the appropriate conditions to justify your answer
(b) What is the sample proportion p̂ for Leslies sample of 150 residents? Round your answer to two decimal places?
(c) What is the probability that more than 98 individuals in the random sample of 150 residents have visited the park in the last month?
Solution:
Given that,
n = 150
b ) = 72% =0. 72
1 - = 1 - 0.72 = 0.28
= = 0. 72
= ( 1 - ) / n
= 0.72 * 0.28 / 150
= 0.0367
= 0.0367
c ) n =150
x =98
= x / n = 98 / 150 = 0.65
P( > 0.65 )
= 1 - P ( < 0.65 )
= 1 - P ( - / ) < ( 0.65 - 0.72 / 0.0367 )
= 1 - P ( z < -0.07 / 0.0367 )
= 1 - P ( z < -1.91 )
Using z table
= 1 - 0.0281
= 0.9719
Probability =0.9719