[YTNUKLR]

gtc is most correct.

Look at 40 up to 49, then 50, 51, 52, etc.

40 - 4 - 0=36

41 - 4 - 1=36

42 - 4 - 2=36

43 - 4 - 3=36

44 - 4 - 4=36

45 - 4 - 5= 36

46 - 4 - 6=36

47 - 4 - 7=36

48 - 4 - 8=36

49 - 4 - 9=36

You could pick 50, 51, 52...

50 - 5 - 0=45

51 - 5 - 1=45

52 - 5 - 2=45

etc.

Thus, there are certain values, {9, 18, 27, 36, 45, 54, 63, 72, 81, 90, 99} that are going to be the result when you pick ANY number. These are all multiples of 9.

Notice how every one of these numbers {9, 18, 27, 36, 45, 54, 63, 72, 81, 90, 99} is the same thing. It is the only gift you are going to imagine. Thus, it just has to show you whatever is in these boxes. And, like Graham says, they change what's in the "multiples of 9" box every time..