By William F. Bultas
These number series puzzles are pretty tough, & if you can solve more than 6 of them, give yourself a pat on the back! The puzzles are not necessarily in order of difficulty, so if one stumps you, you might skip ahead & come back to it later. Feel free to use a calculator when working on the puzzles, but you will find that several of them really don't involve that much in the way of calculations or mathematical knowledge. Lateral thinking is often more important for solving these numeric brain teasers! I have placed the answers on a separate page. If you enjoy these puzzles, try the other tests & puzzles at PUZZ.COM. Have fun!

1. I suppose I should start by saying hello.

23 5 12 3 15 13 ?

2. Something you can see on a calculator by pressing 5 buttons:

3 5 2 9 4 1 1 ?

3. Timing is everything.

100 365 24 60 ?

4. My primary objective is cumulative multiplication. I know, it's an odd objective.

3 10 21 44 65 102 ?

5. Timing, as I mentioned, is everything, & this is true every day of the week.

6 6 7 9 8 6 ?

6. Sometimes numbers are no more than they appear to be.

3 3 5 4 4 3 5 5 4 ?

7. Have I mentioned how important timing is?

7 8 5 5 3 4 4 6 9 7 8 ?

8. Sometimes numbers involve circular logic. Or is it backward logic, or even both?

5 6 2 9 5 1 4 ?

9. At this point, I'm afraid you will accuse me of being fractious.

5 6 7 8 8 8 8 8 ?

10. Alright, I admit it. I am being fractious!

2 15 13 12 12 11 11 ?

11. Looking back on it, this series makes perfect sense.

8 65 293 4472 80291 ?

12. If you have double vision, sometimes things appear unbalanced.

31 53 97 275 451 ?

13. Occasionally things are presented to us in an unusual, yet completely logical order.

2 5 12 23 30 17 8 ?

14. If you have a sixth sense, it may help you to solve this last puzzle: