OK, let's work through this together. We're starting with 285 and we're going to multiply it by 4, which means we add 285 to itself 4 times.
Step 1: 0 + 285 = 285
Step 2: 285 + 285 = 570
Step 3: 570 + 285 = 855
Step 4: 855 + 285 = 1140

So, 285*4 = 1140