Question 1132071
This is a two sample proportion
use z, critical value |z|>1.96
(p hat-p)/sqrt(p*(1-p)/n)), where n = (1/n1)+(1/n2)
the two proportions are 0.683 and 0.785
their difference is -0.102
divide by SE, using combined proportion of 280/380, or 0.737, so SE is sqrt (0.737*0.263)((1/180)+(1/200))
=0.045. This approach pools the two proportions, which is reasonable if the null hypothesis says they are equal, therefore part of the same population.
the z value is 2.27 so reject Ho and conclude the two proportions are different.