Question

The proportion of eligible voters in the State election who will vote for the Premier is assumed to be 53%. What is the probability that in a random sample of 500 voters more than 53% say they will vote for the Premier?

	a.	0.7765
	b.	0.0734
	c.	0.2341
	d.	0.9336
	e.	0.5000

Answer 1

probability=  

Solution

Given that,

p = 0.53

1 - p = 0.47

n = 500

= p =0.53

=  [p( 1 - p ) / n] = [(0.53*0.47) /500 ] = 0.022

P( >0.53 ) = 1 - P( <0.53 )

= 1 - P(( - ) / < (0.53-0.53) /0.022 )

= 1 - P(z <0 )

Using z table

= 1 -0.5000

=0.5000

probability=0.5000