Sample Size Calculator Auditing Is The Difference Between These Sample Measurements Statistically Significant?

Is the difference between these sample measurements statistically significant? - sample size calculator auditing

Firstly, this is not homework, it is a personal interest.

Ratio of 1: 76
Sample 1: 37
Part 2:, 46
Sample 2: 52

I understand that the calculation of statistical significance with this formula, if (P and N content of the sample size):

((P1 * N1) + (P2 * N2)) / (N1 + N2)

And then plug that (in this formula, where V is the result of the above):

(P2-P1) / sqrt (V1 * (1-V1) * ((1/N1) + (1/n2)) ...

For the Z-score, and if the Z-score is greater or less than 1.96 to -1.96 statistically significant (97.5 confidence level is).

I'm confused, because if I formulas not in my data, I get a Z-value of 2.8 - clearly statistically significant. But when using some online calculators (for this: http://www.prconline.com/education/tools ... said it was not significant.

I'm using the wrong procedure, and if so, how should I do instead? Or is the wrong place? What is the Z-Correct Score, and how to get there?