OK, let's work through this together. We're starting with 893 and we're going to multiply it by 4, which means we add 893 to itself 4 times.
Step 1: 0 + 893 = 893
Step 2: 893 + 893 = 1786
Step 3: 1786 + 893 = 2679
Step 4: 2679 + 893 = 3572

So, 893*4 = 3572