Alright, let's solve this math problem step by step. First, we have the number 520. 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 520 and add it to itself 20 times.
Step 1: 0 + 520 = 520
Step 2: 520 + 520 = 1040
Step 3: 1040 + 520 = 1560
Step 4: 1560 + 520 = 2080
Step 5: 2080 + 520 = 2600
Step 6: 2600 + 520 = 3120
Step 7: 3120 + 520 = 3640
Step 8: 3640 + 520 = 4160
Step 9: 4160 + 520 = 4680
Step 10: 4680 + 520 = 5200
Step 11: 5200 + 520 = 5720
Step 12: 5720 + 520 = 6240
Step 13: 6240 + 520 = 6760
Step 14: 6760 + 520 = 7280
Step 15: 7280 + 520 = 7800
Step 16: 7800 + 520 = 8320
Step 17: 8320 + 520 = 8840
Step 18: 8840 + 520 = 9360
Step 19: 9360 + 520 = 9880
Step 20: 9880 + 520 = 10400

So, 520*20 = 10400