mabs239
- 85
- 1
Sorry if it looks too foolish...
1=5
2=25
3=125
4=625
5=?
1=5
2=25
3=125
4=625
5=?
What Could Be the Missing Number?
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- 4,305
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I would say 3125 and it's a no-brainer, although it's hard to tell based on finitely many terms 
jamesb-uk
- 69
- 0
I assume it's 5^5, so 3125.
- 4,305
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Then again, if 1 = 5 it can be anything :)
mabs239
- 85
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CompuChip said:
Yeh, 1=5 and 5=1 ;)
John37
- 11
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3125 right? or is this a no brainer
- 4,305
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So in summary:
- First one could remark that based on 4 terms, it is hard to say something. The sequence might be 5, 25, 125, 625, 125, 25, 5, 25, ... for all we know.
- Anyway, looking at the sequence 5, 25, 125, 625 one would expect 3125.
- Looking at the first line, "1 = 5", one would say that "5 = 1"
- But then one could counter this semi-mathematical argument by a rigorous one, saying that if 1 = 5 then we have a true contradiction, hence we can show that 5 is equal to anything we like.
- First one could remark that based on 4 terms, it is hard to say something. The sequence might be 5, 25, 125, 625, 125, 25, 5, 25, ... for all we know.
- Anyway, looking at the sequence 5, 25, 125, 625 one would expect 3125.
- Looking at the first line, "1 = 5", one would say that "5 = 1"
- But then one could counter this semi-mathematical argument by a rigorous one, saying that if 1 = 5 then we have a true contradiction, hence we can show that 5 is equal to anything we like.