OK, let's work through this together. We're starting with 604 and we're going to multiply it by 28, which means we add 604 to itself 28 times.
Step 1: 0 + 604 = 604
Step 2: 604 + 604 = 1208
Step 3: 1208 + 604 = 1812
Step 4: 1812 + 604 = 2416
Step 5: 2416 + 604 = 3020
Step 6: 3020 + 604 = 3624
Step 7: 3624 + 604 = 4228
Step 8: 4228 + 604 = 4832
Step 9: 4832 + 604 = 5436
Step 10: 5436 + 604 = 6040
Step 11: 6040 + 604 = 6644
Step 12: 6644 + 604 = 7248
Step 13: 7248 + 604 = 7852
Step 14: 7852 + 604 = 8456
Step 15: 8456 + 604 = 9060
Step 16: 9060 + 604 = 9664
Step 17: 9664 + 604 = 10268
Step 18: 10268 + 604 = 10872
Step 19: 10872 + 604 = 11476
Step 20: 11476 + 604 = 12080
Step 21: 12080 + 604 = 12684
Step 22: 12684 + 604 = 13288
Step 23: 13288 + 604 = 13892
Step 24: 13892 + 604 = 14496
Step 25: 14496 + 604 = 15100
Step 26: 15100 + 604 = 15704
Step 27: 15704 + 604 = 16308
Step 28: 16308 + 604 = 16912

So, 604*28 = 16912