Question

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 0.499 .

Answer 1

Solution

Given that,

p = 0.48

1 - p = 1-0.48=0.52

n = 60

= p =0.48

=  [p ( 1 - p ) / n] =   [(0.48*0.52) / 60 ] = 0.064

P( < 0.499) =

= P[( - ) / < (0.499-0.48) / 0.064]

= P(z <0.30 )

Using z table,   

=0.6179