Let's get this math done. We have 891 and we're going to multiply it by 3. This is the same as taking 891 and adding it to itself 3 times.
Step 1: 0 + 891 = 891
Step 2: 891 + 891 = 1782
Step 3: 1782 + 891 = 2673

So, 891*3 = 2673