Add 2 To 11


When can you add 2 to 11 and get 1 as the correct answer?
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   |
   v
Answer:
When you use a clock.  (11 o'clock plus 2 more hours = 1 o'clock)