Let's roll up our sleeves and solve this. We have 11 and we're going to multiply it by 20, essentially adding 11 to itself 20 times.
Step 1: 0 + 11 = 11
Step 2: 11 + 11 = 22
Step 3: 22 + 11 = 33
Step 4: 33 + 11 = 44
Step 5: 44 + 11 = 55
Step 6: 55 + 11 = 66
Step 7: 66 + 11 = 77
Step 8: 77 + 11 = 88
Step 9: 88 + 11 = 99
Step 10: 99 + 11 = 110
Step 11: 110 + 11 = 121
Step 12: 121 + 11 = 132
Step 13: 132 + 11 = 143
Step 14: 143 + 11 = 154
Step 15: 154 + 11 = 165
Step 16: 165 + 11 = 176
Step 17: 176 + 11 = 187
Step 18: 187 + 11 = 198
Step 19: 198 + 11 = 209
Step 20: 209 + 11 = 220

So, 11*20 = 220