OK, let's work through this together. We're starting with 48 and we're going to multiply it by 4, which means we add 48 to itself 4 times.
Step 1: 0 + 48 = 48
Step 2: 48 + 48 = 96
Step 3: 96 + 48 = 144
Step 4: 144 + 48 = 192

So, 48*4 = 192