OK, let's work through this together. We're starting with 858 and we're going to multiply it by 16, which means we add 858 to itself 16 times.
Step 1: 0 + 858 = 858
Step 2: 858 + 858 = 1716
Step 3: 1716 + 858 = 2574
Step 4: 2574 + 858 = 3432
Step 5: 3432 + 858 = 4290
Step 6: 4290 + 858 = 5148
Step 7: 5148 + 858 = 6006
Step 8: 6006 + 858 = 6864
Step 9: 6864 + 858 = 7722
Step 10: 7722 + 858 = 8580
Step 11: 8580 + 858 = 9438
Step 12: 9438 + 858 = 10296
Step 13: 10296 + 858 = 11154
Step 14: 11154 + 858 = 12012
Step 15: 12012 + 858 = 12870
Step 16: 12870 + 858 = 13728

So, 858*16 = 13728