In: Statistics and Probability
it has been reported that 48% of people text and drive. A random sample of 60 drivers is drawn. Find the probability that the proportion of people in the sample who text and drive is less than 0.498.
Solution:
Given that,
n = 60
= 48% =0.48
1 - 
 = 1 - 0.48 = 0.52

=  
= 0.48

= 
( 1 - 
 ) / n

=  0.48
* 0.52 / 60
= 0.0645

= 0.0645
p (  
< 0.498 )
p ( 
 -   
/ 
) < ( 0.498 - 0.48 / 0.0645 )
p ( z < 0.018 / 0.0645 )
Using z table
p ( z < 0.28 )
= 0.6103
Probability = 0.6103