Hi,
Are there any shortcuts for dividing, say, 38,400 by 1,920? It's not really those numbers that I'm asking about, but the principle per se.
Thanks

It depends on the particular numbers. You can always just do the long division, which won't take an inordinate amount of time, but there are other options. In this case, for example, you could eliminate the final zero from each number and reduce the fraction. If you plan to do so, however, make certain to learn your rules of divisibility (Number Properties Strategy Guide).

Also, if the problem specifically asks you to approximate, do so! In this problem, 38,400 is about 40,000, and 1,920 is about 2,000, so the answer is approximately 20.

Hope that helps!
-dan