What's Your IQ?

[jaywood]

Got a 136... but I've got a missed question under protest! I'll ask the collective brain trust here to see if I've got a secondary solution to the question. Here is the problem that was on the test:

Which one of the numbers in the series is wrong, and should be replaced?

2 - 4 - 8 - 16 - 20 - 22 - 44 - 46


The answer THEY gave was to replace the 16 with a 10 and the sequence would be +2, x2, +2, x2... etc. The solution I gave was to replace the 20 with an 18 and the sequence would then be +2, +4, x2, +2, +4, x2 etc. Am I seeing this incorrectly or does there happen to be more than one way to skin this cat?

[BigguyZ]

16. Work backwards. 46-2=44. 44/2=22. 22-2=20. 20/2=10. 10-2= 8. 8/2=4. 4-2=2.

It's an algorithm of two different functions. It took me a bit to realize, but I tried working backwards and that worked.

[JTimmons]

I gave them a co-workers email address! It'll give him something to do other than surfing you tube!

[TheRic]

.... Am I seeing this incorrectly or does there happen to be more than one way to skin this cat?

It's not uncommon for some questions like this to have more than one answer. If it was a real test being graded by a person the grader might have given you credit, might not have.

The only problem with your answer is that the pattern begins again at the end. Normally the sequence of numbers would stop at the end of the pattern, not in the middle of the pattern.

[Alex Franke]

The solution I gave was to replace the 20 with an 18 and the sequence would then be +2, +4, x2, +2, +4, x2 etc. Am I seeing this incorrectly or does there happen to be more than one way to skin this cat?

Excellent -- that's totally impressive that you came up with that. They'd probably break out that annoying "best answer" clause, though, if you challenged it. (Why do a set of three operations when you can do a set of two?)