Alright, let's solve this math problem step by step. First, we have the number 312. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 20. So, we're going to take the number 312 and add it to itself 20 times.
Step 1: 0 + 312 = 312
Step 2: 312 + 312 = 624
Step 3: 624 + 312 = 936
Step 4: 936 + 312 = 1248
Step 5: 1248 + 312 = 1560
Step 6: 1560 + 312 = 1872
Step 7: 1872 + 312 = 2184
Step 8: 2184 + 312 = 2496
Step 9: 2496 + 312 = 2808
Step 10: 2808 + 312 = 3120
Step 11: 3120 + 312 = 3432
Step 12: 3432 + 312 = 3744
Step 13: 3744 + 312 = 4056
Step 14: 4056 + 312 = 4368
Step 15: 4368 + 312 = 4680
Step 16: 4680 + 312 = 4992
Step 17: 4992 + 312 = 5304
Step 18: 5304 + 312 = 5616
Step 19: 5616 + 312 = 5928
Step 20: 5928 + 312 = 6240

So, 312*20 = 6240