OK, let's work through this together. We're starting with 723 and we're going to multiply it by 3, which means we add 723 to itself 3 times.
Step 1: 0 + 723 = 723
Step 2: 723 + 723 = 1446
Step 3: 1446 + 723 = 2169

So, 723*3 = 2169