OK, let's work through this together. We're starting with 85 and we're going to multiply it by 4, which means we add 85 to itself 4 times.
Step 1: 0 + 85 = 85
Step 2: 85 + 85 = 170
Step 3: 170 + 85 = 255
Step 4: 255 + 85 = 340

So, 85*4 = 340