Question

A preliminary survey shows that 33% of college students smoke. In a class of 43 students, what is the probability that more than 48% of the students smoke? Use Appendix B.1 for the z-values. (Round the z-value to 2 decimal places and the final answer to 4 decimal places.) Probability

Answer 1

Solution:

Given that,

n = 43

= 0.33

1 - = 1 - 0.33 = 0.67

So,

a ) =   = 0.33

= ( 1 - ) / n

=  0.33 * 0.67 / 43

= 0.0717

= 0.0717

p (   > 0.48 )

= 1 -  p (   < 0.48 )

= 1 - p ( -    / ) < ( 0.48 - 0.33 / 0.0717 )

= 1 - p ( z < 2.09 / 0.0717 )

= 1 - p ( z < 2.09 )

Using z table

= 1 - 0.9817

= 0.0183

Probability = 0.0183