In the mass death at the end of Parashas Balak, how many people died before Pinchas killed Zimri?
Aside from the people who died in the plague, though, you might also have to consider the ones who were executed judicially. Moshe instructs the judges, "Each of you kill his people who are attached to Baal Peor," and Rashi there (citing Yerushalmi, Sanhedrin 10:2) explains that there were 78,600 judges, each of whom was to judge and kill two of the sinners. That would then make 157,200 people who were executed plus 24,000 who died from the plague.
This guy goes still further, and argues that mathematically, the number of people executed was 222,142. I haven't checked his math, though.
This is all according to Rashi and the Yerushalmi. Ramban there, though, argues that these executions never actually took place, because they were forestalled either by the plague or by Pinchas' brave action - and that Hashem dealt with these sinners later on.
וַיִּהְיוּ, הַמֵּתִים בַּמַּגֵּפָה--אַרְבָּעָה וְעֶשְׂרִים, אָלֶף.
And those that died by the plague were twenty and four thousand.