In the chess world championship, 15 matches take place between the top two ranked players in the world. How many ways can a person predict exactly 12 results (win, draw and loss) right?

There are three results - win, draw, loss

Select the 12 matches in $$^{15}C_{12}$$ ways. For these, the correct prediction is possible in only 1 way.
For each of the other three matches, a wrong prediction can be done in 2 ways. So, total number of ways of predicting wrong = $$2^3$$

Total number of ways = $$^{15}C_{12}$$*$$2^3$$ = 3640 ways