Sure thing! We've got 111 and we're gonna multiply it by 9. That's the same as adding 111 to itself 9 times.
Step 1: 0 + 111 = 111
Step 2: 111 + 111 = 222
Step 3: 222 + 111 = 333
Step 4: 333 + 111 = 444
Step 5: 444 + 111 = 555
Step 6: 555 + 111 = 666
Step 7: 666 + 111 = 777
Step 8: 777 + 111 = 888
Step 9: 888 + 111 = 999

So, 111*9 = 999