SOLUTION: Let n1 = 100, X1 = 50, n2 = 100, and X2 = 30. a. At the 0.05 level of significance, is there evidence of a significant difference between the two population proportions?

Algebra ->  Probability-and-statistics -> SOLUTION: Let n1 = 100, X1 = 50, n2 = 100, and X2 = 30. a. At the 0.05 level of significance, is there evidence of a significant difference between the two population proportions?      Log On


   



Question 1182639: Let n1 = 100, X1 = 50, n2 = 100, and X2 = 30.
a. At the 0.05 level of significance, is there evidence of a significant difference between the two population proportions?

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
This would be a two sample proportion assuming that this is approximately normally distributed.
Ho: p1=p2
Ha: p1 NE p2
alpha =0.05 p{reject Ho|Ho true}. Reject Ho if |z|>1.96
z=(0.5-0.3)/sqrt(0.4.*0.6/100+(0.4*0.6)/100), using 40% as combined proportion (80/200)
=0.2/sqrt(0.0048)
=2.89
reject Ho: The two proportions are significantly different, which is another way of saying they came from two different populations.
p-value=0.004