OK, let's work through this together. We're starting with 672 and we're going to multiply it by 16, which means we add 672 to itself 16 times.
Step 1: 0 + 672 = 672
Step 2: 672 + 672 = 1344
Step 3: 1344 + 672 = 2016
Step 4: 2016 + 672 = 2688
Step 5: 2688 + 672 = 3360
Step 6: 3360 + 672 = 4032
Step 7: 4032 + 672 = 4704
Step 8: 4704 + 672 = 5376
Step 9: 5376 + 672 = 6048
Step 10: 6048 + 672 = 6720
Step 11: 6720 + 672 = 7392
Step 12: 7392 + 672 = 8064
Step 13: 8064 + 672 = 8736
Step 14: 8736 + 672 = 9408
Step 15: 9408 + 672 = 10080
Step 16: 10080 + 672 = 10752

So, 672*16 = 10752