When taking an IQ test, the set of numbers given is:
17, 12, 108, 9.
You are supposed to work out which number does not fit. I have earmarked 17 as the incorrect number for two different reasons: it's the only number not divisible by 3, and it's the only number not divisible by another number in the sequence (i.e. 108÷12=9) - but the test keeps saying that's not the correct answer.
Please help me determine which number does not fit, and why.
As @Randal'Thor mentioned in the comments, it's not fully clear whether this is simply a set of numbers or really a sequence where order matters. Since it is not asked for the next number, this looks to me more like a simple "odd one out". For me there is no "obvious" solution and I am sure you could think of many more reasons why one number is the "odd one out".
17:
- it is the only prime number
- it's the only number with an even cross sum
12:
- the last digits are increasing 7,8,9 but the 2 of 12 doesn't fit
108:
- as @IlCorsaroNero mentioned it's the only number increasing the otherwise falling sequence
9:
- because it is the only number which doesn't start with 1
For me the incorrect number is :
108 because the number are decrease but 108 is the only number the increase the sequence.
