OK, let's crack this. We're given 750 and our task is to multiply it by 91. Essentially, we'll be adding 750 to itself 91 times.
Step 1: 0 + 750 = 750
Step 2: 750 + 750 = 1500
Step 3: 1500 + 750 = 2250
Step 4: 2250 + 750 = 3000
Step 5: 3000 + 750 = 3750
Step 6: 3750 + 750 = 4500
Step 7: 4500 + 750 = 5250
Step 8: 5250 + 750 = 6000
Step 9: 6000 + 750 = 6750
Step 10: 6750 + 750 = 7500
Step 11: 7500 + 750 = 8250
Step 12: 8250 + 750 = 9000
Step 13: 9000 + 750 = 9750
Step 14: 9750 + 750 = 10500
Step 15: 10500 + 750 = 11250
Step 16: 11250 + 750 = 12000
Step 17: 12000 + 750 = 12750
Step 18: 12750 + 750 = 13500
Step 19: 13500 + 750 = 14250
Step 20: 14250 + 750 = 15000
Step 21: 15000 + 750 = 15750
Step 22: 15750 + 750 = 16500
Step 23: 16500 + 750 = 17250
Step 24: 17250 + 750 = 18000
Step 25: 18000 + 750 = 18750
Step 26: 18750 + 750 = 19500
Step 27: 19500 + 750 = 20250
Step 28: 20250 + 750 = 21000
Step 29: 21000 + 750 = 21750
Step 30: 21750 + 750 = 22500
Step 31: 22500 + 750 = 23250
Step 32: 23250 + 750 = 24000
Step 33: 24000 + 750 = 24750
Step 34: 24750 + 750 = 25500
Step 35: 25500 + 750 = 26250
Step 36: 26250 + 750 = 27000
Step 37: 27000 + 750 = 27750
Step 38: 27750 + 750 = 28500
Step 39: 28500 + 750 = 29250
Step 40: 29250 + 750 = 30000
Step 41: 30000 + 750 = 30750
Step 42: 30750 + 750 = 31500
Step 43: 31500 + 750 = 32250
Step 44: 32250 + 750 = 33000
Step 45: 33000 + 750 = 33750
Step 46: 33750 + 750 = 34500
Step 47: 34500 + 750 = 35250
Step 48: 35250 + 750 = 36000
Step 49: 36000 + 750 = 36750
Step 50: 36750 + 750 = 37500
Step 51: 37500 + 750 = 38250
Step 52: 38250 + 750 = 39000
Step 53: 39000 + 750 = 39750
Step 54: 39750 + 750 = 40500
Step 55: 40500 + 750 = 41250
Step 56: 41250 + 750 = 42000
Step 57: 42000 + 750 = 42750
Step 58: 42750 + 750 = 43500
Step 59: 43500 + 750 = 44250
Step 60: 44250 + 750 = 45000
Step 61: 45000 + 750 = 45750
Step 62: 45750 + 750 = 46500
Step 63: 46500 + 750 = 47250
Step 64: 47250 + 750 = 48000
Step 65: 48000 + 750 = 48750
Step 66: 48750 + 750 = 49500
Step 67: 49500 + 750 = 50250
Step 68: 50250 + 750 = 51000
Step 69: 51000 + 750 = 51750
Step 70: 51750 + 750 = 52500
Step 71: 52500 + 750 = 53250
Step 72: 53250 + 750 = 54000
Step 73: 54000 + 750 = 54750
Step 74: 54750 + 750 = 55500
Step 75: 55500 + 750 = 56250
Step 76: 56250 + 750 = 57000
Step 77: 57000 + 750 = 57750
Step 78: 57750 + 750 = 58500
Step 79: 58500 + 750 = 59250
Step 80: 59250 + 750 = 60000
Step 81: 60000 + 750 = 60750
Step 82: 60750 + 750 = 61500
Step 83: 61500 + 750 = 62250
Step 84: 62250 + 750 = 63000
Step 85: 63000 + 750 = 63750
Step 86: 63750 + 750 = 64500
Step 87: 64500 + 750 = 65250
Step 88: 65250 + 750 = 66000
Step 89: 66000 + 750 = 66750
Step 90: 66750 + 750 = 67500
Step 91: 67500 + 750 = 68250

So, 750*91 = 68250