Let's roll up our sleeves and solve this. We have 309 and we're going to multiply it by 28, essentially adding 309 to itself 28 times.
Step 1: 0 + 309 = 309
Step 2: 309 + 309 = 618
Step 3: 618 + 309 = 927
Step 4: 927 + 309 = 1236
Step 5: 1236 + 309 = 1545
Step 6: 1545 + 309 = 1854
Step 7: 1854 + 309 = 2163
Step 8: 2163 + 309 = 2472
Step 9: 2472 + 309 = 2781
Step 10: 2781 + 309 = 3090
Step 11: 3090 + 309 = 3399
Step 12: 3399 + 309 = 3708
Step 13: 3708 + 309 = 4017
Step 14: 4017 + 309 = 4326
Step 15: 4326 + 309 = 4635
Step 16: 4635 + 309 = 4944
Step 17: 4944 + 309 = 5253
Step 18: 5253 + 309 = 5562
Step 19: 5562 + 309 = 5871
Step 20: 5871 + 309 = 6180
Step 21: 6180 + 309 = 6489
Step 22: 6489 + 309 = 6798
Step 23: 6798 + 309 = 7107
Step 24: 7107 + 309 = 7416
Step 25: 7416 + 309 = 7725
Step 26: 7725 + 309 = 8034
Step 27: 8034 + 309 = 8343
Step 28: 8343 + 309 = 8652

So, 309*28 = 8652