OK, let's work through this together. We're starting with 788 and we're going to multiply it by 4, which means we add 788 to itself 4 times.
Step 1: 0 + 788 = 788
Step 2: 788 + 788 = 1576
Step 3: 1576 + 788 = 2364
Step 4: 2364 + 788 = 3152

So, 788*4 = 3152