Question about sig figs

Sometimes the problems my teachers assign me would have only 1 signifigant figure because something like 5m is thrown in there. So instead of the answer being 87,451, the answer would be 9.0 *10^4. That's a lot of information lost. My question is how do I deal with sig figs when there's numbers in the problem that would make the answer have one signifigant digit? Should I just have 1 sig fig in my answer or should I always strive to have answers with a minimum number of digits like 3 or something?