OK, let's work through this together. We're starting with 453 and we're going to multiply it by 4, which means we add 453 to itself 4 times.
Step 1: 0 + 453 = 453
Step 2: 453 + 453 = 906
Step 3: 906 + 453 = 1359
Step 4: 1359 + 453 = 1812

So, 453*4 = 1812