Let's roll up our sleeves and solve this. We have 170 and we're going to multiply it by 5, essentially adding 170 to itself 5 times.
Step 1: 0 + 170 = 170
Step 2: 170 + 170 = 340
Step 3: 340 + 170 = 510
Step 4: 510 + 170 = 680
Step 5: 680 + 170 = 850

So, 170*5 = 850