Let's get this math done. We have 75 and we're going to multiply it by 15. This is the same as taking 75 and adding it to itself 15 times.
Step 1: 0 + 75 = 75
Step 2: 75 + 75 = 150
Step 3: 150 + 75 = 225
Step 4: 225 + 75 = 300
Step 5: 300 + 75 = 375
Step 6: 375 + 75 = 450
Step 7: 450 + 75 = 525
Step 8: 525 + 75 = 600
Step 9: 600 + 75 = 675
Step 10: 675 + 75 = 750
Step 11: 750 + 75 = 825
Step 12: 825 + 75 = 900
Step 13: 900 + 75 = 975
Step 14: 975 + 75 = 1050
Step 15: 1050 + 75 = 1125

So, 75*15 = 1125