Mental Challenges -- Puzzles To Solve

[David]

Does anyone like mental challenges like logic puzzles? My friend Chris has created a bunch of these, & I'd like to share them here. They're pretty fun to try to solve--not very hard. I'll post solutions after a few days (unless someone else beats me to it).

Mental Challenge #1: Answer the following riddle.

20  18  21  5   15  18   6  1  12  19  5:
3  1  14   25  15  21
4  5  3  9  16  8  5  18   13  5?

[LukeA]

That's not a "true or false" question.

[Ench]

6 1 18 20 15 15 5 1 19 25

[David]

6 1 18 20 15 15 5 1 19 25Well, they will get a little tougher!