You know that chalcopyrite is
That is what percent concentration by mass tells you. That
So, you know that you get
You can use the ore's percent concentration by mass as a conversion factor to help you calculate the mass of ore that would contain that many grams of copper
#321.5 color(red)(cancel(color(black)("g Cu"))) * "100 g ore"/(34.63color(red)(cancel(color(black)("g Cu")))) = color(green)(bar(ul(|color(white)(a/a)color(black)("928.4 g ore")color(white)(a/a)|)))#
The answer is rounded to four sig figs.