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