thanks reiny--but i'm in 6th gr and we r not studying powers..can you help me with a simpler answer without powers?

are you referring to

http://www.jiskha.com/display.cgi?id=1258079199 ?

instead of km^2 we could call it square km.
The way the question was worded, that's what we get, there is no way around it.

Perhaps if you tell me where the
3km x 200m x 5 came from, another approach might be used.