OK, let's work through this together. We're starting with 398 and we're going to multiply it by 4, which means we add 398 to itself 4 times.
Step 1: 0 + 398 = 398
Step 2: 398 + 398 = 796
Step 3: 796 + 398 = 1194
Step 4: 1194 + 398 = 1592

So, 398*4 = 1592