Find the value of z that would be used to test the difference between the proportions, given the following. (Use G - H. Give your answer correct to two decimal places.)

Sample n x
G 386 327
H 414 321

.

4 answers

Which one is n , x
Sample n x
G 386 327
H 414 321
Sorry it keeps going together
Samples are G & H
N =386, 414
X =327, 321
n1 = 386
n1 = 414

x1 = 327
x2 = 321

phat1= x1/n2 = 327/386 = .847

phat2 = x2/n2 = 321/414 = .775

Pbar = (x1+x2) /(n1 + n2) = (327+ 321)/(386+414)

pbar = .81

qbar = 1- pbar = .19

z = (phat1-phat2)/(sqrt(pbar *qbar/n1 + pbar *qbar/n2)

z = (.847-775)/(sqrt (.81*.19/386 + .81*.19/414))

z = .072/.02776 = 2.59