I purchased a Hinkley wall mount 3-light fixture that has wires coming out of two areas on the fixture -both on the back (wall) side. The left one has 2 black and 2 white wires and the right has 1 black and 1 white. There are three wires coming out of the wall - 2 black and 1 white. Any ideas as to how the two sets of wires on the fixture should hook up to the wires coming out of the wall? Thank you.