Let's roll up our sleeves and solve this. We have 888 and we're going to multiply it by 31, essentially adding 888 to itself 31 times.
Step 1: 0 + 888 = 888
Step 2: 888 + 888 = 1776
Step 3: 1776 + 888 = 2664
Step 4: 2664 + 888 = 3552
Step 5: 3552 + 888 = 4440
Step 6: 4440 + 888 = 5328
Step 7: 5328 + 888 = 6216
Step 8: 6216 + 888 = 7104
Step 9: 7104 + 888 = 7992
Step 10: 7992 + 888 = 8880
Step 11: 8880 + 888 = 9768
Step 12: 9768 + 888 = 10656
Step 13: 10656 + 888 = 11544
Step 14: 11544 + 888 = 12432
Step 15: 12432 + 888 = 13320
Step 16: 13320 + 888 = 14208
Step 17: 14208 + 888 = 15096
Step 18: 15096 + 888 = 15984
Step 19: 15984 + 888 = 16872
Step 20: 16872 + 888 = 17760
Step 21: 17760 + 888 = 18648
Step 22: 18648 + 888 = 19536
Step 23: 19536 + 888 = 20424
Step 24: 20424 + 888 = 21312
Step 25: 21312 + 888 = 22200
Step 26: 22200 + 888 = 23088
Step 27: 23088 + 888 = 23976
Step 28: 23976 + 888 = 24864
Step 29: 24864 + 888 = 25752
Step 30: 25752 + 888 = 26640
Step 31: 26640 + 888 = 27528

So, 888*31 = 27528