Alright, let's solve this math problem step by step. First, we have the number 787. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 40. So, we're going to take the number 787 and add it to itself 40 times.
Step 1: 0 + 787 = 787
Step 2: 787 + 787 = 1574
Step 3: 1574 + 787 = 2361
Step 4: 2361 + 787 = 3148
Step 5: 3148 + 787 = 3935
Step 6: 3935 + 787 = 4722
Step 7: 4722 + 787 = 5509
Step 8: 5509 + 787 = 6296
Step 9: 6296 + 787 = 7083
Step 10: 7083 + 787 = 7870
Step 11: 7870 + 787 = 8657
Step 12: 8657 + 787 = 9444
Step 13: 9444 + 787 = 10231
Step 14: 10231 + 787 = 11018
Step 15: 11018 + 787 = 11805
Step 16: 11805 + 787 = 12592
Step 17: 12592 + 787 = 13379
Step 18: 13379 + 787 = 14166
Step 19: 14166 + 787 = 14953
Step 20: 14953 + 787 = 15740
Step 21: 15740 + 787 = 16527
Step 22: 16527 + 787 = 17314
Step 23: 17314 + 787 = 18101
Step 24: 18101 + 787 = 18888
Step 25: 18888 + 787 = 19675
Step 26: 19675 + 787 = 20462
Step 27: 20462 + 787 = 21249
Step 28: 21249 + 787 = 22036
Step 29: 22036 + 787 = 22823
Step 30: 22823 + 787 = 23610
Step 31: 23610 + 787 = 24397
Step 32: 24397 + 787 = 25184
Step 33: 25184 + 787 = 25971
Step 34: 25971 + 787 = 26758
Step 35: 26758 + 787 = 27545
Step 36: 27545 + 787 = 28332
Step 37: 28332 + 787 = 29119
Step 38: 29119 + 787 = 29906
Step 39: 29906 + 787 = 30693
Step 40: 30693 + 787 = 31480

So, 787*40 = 31480