Alright, let's solve this math problem step by step. First, we have the number 858. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 5. So, we're going to take the number 858 and add it to itself 5 times.
Step 1: 0 + 858 = 858
Step 2: 858 + 858 = 1716
Step 3: 1716 + 858 = 2574
Step 4: 2574 + 858 = 3432
Step 5: 3432 + 858 = 4290

So, 858*5 = 4290