Let's roll up our sleeves and solve this. We have 823 and we're going to multiply it by 3, essentially adding 823 to itself 3 times.
Step 1: 0 + 823 = 823
Step 2: 823 + 823 = 1646
Step 3: 1646 + 823 = 2469

So, 823*3 = 2469