I'm guessing that your question concerns the bonus earned by being a Silver, Gold, or Platinum elite member. Normally, one earns 10 points (5 at Residence Inn & TownPlace Suites) per dollar spent. Silver elite status adds a 20% bonus, Gold gives 25% bonus, and Platinum earns a 50% bonus.
For most Marriott brands you will earn only on the room rate, but for the higher end brands you earn points for every dollar spent.
So as a Silver Elite member, you will get the base points, plus a 20% bonus.