Let's roll up our sleeves and solve this. We have 236 and we're going to multiply it by 51, essentially adding 236 to itself 51 times.
Step 1: 0 + 236 = 236
Step 2: 236 + 236 = 472
Step 3: 472 + 236 = 708
Step 4: 708 + 236 = 944
Step 5: 944 + 236 = 1180
Step 6: 1180 + 236 = 1416
Step 7: 1416 + 236 = 1652
Step 8: 1652 + 236 = 1888
Step 9: 1888 + 236 = 2124
Step 10: 2124 + 236 = 2360
Step 11: 2360 + 236 = 2596
Step 12: 2596 + 236 = 2832
Step 13: 2832 + 236 = 3068
Step 14: 3068 + 236 = 3304
Step 15: 3304 + 236 = 3540
Step 16: 3540 + 236 = 3776
Step 17: 3776 + 236 = 4012
Step 18: 4012 + 236 = 4248
Step 19: 4248 + 236 = 4484
Step 20: 4484 + 236 = 4720
Step 21: 4720 + 236 = 4956
Step 22: 4956 + 236 = 5192
Step 23: 5192 + 236 = 5428
Step 24: 5428 + 236 = 5664
Step 25: 5664 + 236 = 5900
Step 26: 5900 + 236 = 6136
Step 27: 6136 + 236 = 6372
Step 28: 6372 + 236 = 6608
Step 29: 6608 + 236 = 6844
Step 30: 6844 + 236 = 7080
Step 31: 7080 + 236 = 7316
Step 32: 7316 + 236 = 7552
Step 33: 7552 + 236 = 7788
Step 34: 7788 + 236 = 8024
Step 35: 8024 + 236 = 8260
Step 36: 8260 + 236 = 8496
Step 37: 8496 + 236 = 8732
Step 38: 8732 + 236 = 8968
Step 39: 8968 + 236 = 9204
Step 40: 9204 + 236 = 9440
Step 41: 9440 + 236 = 9676
Step 42: 9676 + 236 = 9912
Step 43: 9912 + 236 = 10148
Step 44: 10148 + 236 = 10384
Step 45: 10384 + 236 = 10620
Step 46: 10620 + 236 = 10856
Step 47: 10856 + 236 = 11092
Step 48: 11092 + 236 = 11328
Step 49: 11328 + 236 = 11564
Step 50: 11564 + 236 = 11800
Step 51: 11800 + 236 = 12036

So, 236*51 = 12036