I would use chi-square if I was in business and wanted to see if a new sales strategy worked or not. If I were to use chi-square, I would construct the experiment with a control group and a treatment group. The control group was exposed to the present sales strategy, whereas the treatment group was exposed to the new sales approach. I would next compare the outcomes of the two groups to see whether there was a statistically significant difference.

What would be the variables being measure in the chi-square example you mentioned above