Lol. But really, that "numbers can be anything they want to be" and "everybody's right" crap cripples, not empowers people.
Warning: not being able to complete the sequence exposes you to
schizophrenia,
low income, lower work performance*,
violent behavior and supporting multiple intelligences theory
p.s. yes, going by Athenian200's explanation, those numbers are most often encountered in the situation in question, and repeating it in an IQ test (if a person is capable of that - not easy) - is what gives people high scores. As high as genius scores.
The tests really have many options that are "possible", others with a twisted logic, others with unusual logic, others with unproductive logic, etc. Now it is
*THERE* that the intelligence is measured; who finds the most productive logic, most logical logic, etc. One has to decide themselves the logic they use to choose the logic, and think how far they would get with it. The correct answer in good tests (most of them) is almost always the logic that gets one farthest.
*Hunter, J. E. and Hunter, R. F. (1984). Validity and utility of alternative predictors of job performance. Psychological Bulletin, 96, 72–98.