Help on Potium Iodide & Lead Nitrate Lab?

I have 1.5 grams of Potium Iodide and 1.5 grams of Lead Nitrate and we mixed them and then filter it through filter paper. We had .18 grams of filter paper. The dish weighed 76.6 grams. After we drained it and dried it over night it weighed 80.6 grams and without the dish and filter paper it would weigh 3.82 grams. What would be the theoretical yield of the precipitate (how many grams of product should be formed) and determine the percent yield (the percent of the theoretical yield that you got) Also if you could explain how you got the answer that would be great! thanks!