Without delay, let's solve this. We've got 636 and we will be multiplying it by 3, that is, adding 636 to itself 3 times.
Step 1: 0 + 636 = 636
Step 2: 636 + 636 = 1272
Step 3: 1272 + 636 = 1908

So, 636*3 = 1908