OK, let's work through this together. We're starting with 958 and we're going to multiply it by 40, which means we add 958 to itself 40 times.
Step 1: 0 + 958 = 958
Step 2: 958 + 958 = 1916
Step 3: 1916 + 958 = 2874
Step 4: 2874 + 958 = 3832
Step 5: 3832 + 958 = 4790
Step 6: 4790 + 958 = 5748
Step 7: 5748 + 958 = 6706
Step 8: 6706 + 958 = 7664
Step 9: 7664 + 958 = 8622
Step 10: 8622 + 958 = 9580
Step 11: 9580 + 958 = 10538
Step 12: 10538 + 958 = 11496
Step 13: 11496 + 958 = 12454
Step 14: 12454 + 958 = 13412
Step 15: 13412 + 958 = 14370
Step 16: 14370 + 958 = 15328
Step 17: 15328 + 958 = 16286
Step 18: 16286 + 958 = 17244
Step 19: 17244 + 958 = 18202
Step 20: 18202 + 958 = 19160
Step 21: 19160 + 958 = 20118
Step 22: 20118 + 958 = 21076
Step 23: 21076 + 958 = 22034
Step 24: 22034 + 958 = 22992
Step 25: 22992 + 958 = 23950
Step 26: 23950 + 958 = 24908
Step 27: 24908 + 958 = 25866
Step 28: 25866 + 958 = 26824
Step 29: 26824 + 958 = 27782
Step 30: 27782 + 958 = 28740
Step 31: 28740 + 958 = 29698
Step 32: 29698 + 958 = 30656
Step 33: 30656 + 958 = 31614
Step 34: 31614 + 958 = 32572
Step 35: 32572 + 958 = 33530
Step 36: 33530 + 958 = 34488
Step 37: 34488 + 958 = 35446
Step 38: 35446 + 958 = 36404
Step 39: 36404 + 958 = 37362
Step 40: 37362 + 958 = 38320

So, 958*40 = 38320