Let's roll up our sleeves and solve this. We have 837 and we're going to multiply it by 4, essentially adding 837 to itself 4 times.
Step 1: 0 + 837 = 837
Step 2: 837 + 837 = 1674
Step 3: 1674 + 837 = 2511
Step 4: 2511 + 837 = 3348

So, 837*4 = 3348