A few things.

1) You haven't actually written anything to your file.

2) You really never want to use doubles or floats for monetary quantities. The rounding errors will kill you. Much better to use a dedicated Currency class that uses fixed point arithmetic, though for this exercise it probably doesn't matter.

3) It's usually good programming practice to give constants names rather than embedding literals, but, again, for this exercise it probably doesn't matter.

Other than that it appears to be good, especially if this is your first time trying to write a Java program.