OK, let's work through this together. We're starting with 36 and we're going to multiply it by 19, which means we add 36 to itself 19 times.
Step 1: 0 + 36 = 36
Step 2: 36 + 36 = 72
Step 3: 72 + 36 = 108
Step 4: 108 + 36 = 144
Step 5: 144 + 36 = 180
Step 6: 180 + 36 = 216
Step 7: 216 + 36 = 252
Step 8: 252 + 36 = 288
Step 9: 288 + 36 = 324
Step 10: 324 + 36 = 360
Step 11: 360 + 36 = 396
Step 12: 396 + 36 = 432
Step 13: 432 + 36 = 468
Step 14: 468 + 36 = 504
Step 15: 504 + 36 = 540
Step 16: 540 + 36 = 576
Step 17: 576 + 36 = 612
Step 18: 612 + 36 = 648
Step 19: 648 + 36 = 684

So, 36*19 = 684