It's been a few years since I've done any Java work, but most languages work the same, so I think we're safe. Still, assuming I'm rambling incoherently and testing everything I suggest wouldn't be the worst idea in the world...
The big operator for arrays is indexing. If you have an array A with five integers, then you have five elements: A[0], A[1], A[2], A[3], A[4]; each of these acts just like a normal integer (or whatever) variable (or object). Your FOR loop (in getTotal) is giving you the indices in order. From there, adding them should be obvious and averaging them the same...but if it isn't, I should be checking e-mail on and off for another half hour or so and my direct address should be accessible over to the left.