Let's roll up our sleeves and solve this. We have 890 and we're going to multiply it by 5, essentially adding 890 to itself 5 times.
Step 1: 0 + 890 = 890
Step 2: 890 + 890 = 1780
Step 3: 1780 + 890 = 2670
Step 4: 2670 + 890 = 3560
Step 5: 3560 + 890 = 4450

So, 890*5 = 4450