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How to find the missing number

$\{14,36,25,25\},\{20,50,20,10\},\{36,54,7,?\}$

answer was $3$ , but I dont understand why?

well these four sets of numbers were kept in four seperate circular plate and the plates were divided in four part.

Belgi
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Myshkin
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    Hint: see what each set sums to :-) – obataku Aug 31 '13 at 20:42
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    I don't really like this question, or any pattern recognition question. You have to try and find similarities between the known elements and assume that the pattern you've noticed continues. While they are interesting puzzles, they aren't really mathematical, at least from my point of view. A perfect example of the type of puzzle I'm talking about is "Find the next number in the sequence $1, 1, 2, 3, 5, 8, \dots$" As can be seen here, there are lots of possible answers and reasons for them. – Michael Albanese Aug 31 '13 at 20:51
  • Having said that, I don't think this question is out of place on MSE. – Michael Albanese Aug 31 '13 at 20:51
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    @Michael I do think it is out of place, for the reason you gave. At the very least it should be community wiki (if I understand the rules correctly) because there is no single mathematically correct answer. – Trevor Wilson Aug 31 '13 at 20:58
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    @TrevorWilson: I somewhat agree. I suppose here because the 'correct' answer is given, our options are restricted. However, there still could be multiple reasons why the answer is what it is. I suppose why I don't think it is out of place is that often the patterns in such questions are mathematical in nature. If such questions are rightly given the puzzle tag, which Belgi made sure of, I think they are OK. If anyone feels the need to discuss the issue further, it is probably best to start a meta post rather than continuing here. – Michael Albanese Aug 31 '13 at 21:05
  • Does the circular plates look like Pie charts? If that is the case, then the answer is unambiguous. – achille hui Aug 31 '13 at 21:21

2 Answers2

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Hint: What is the sum of the elements in the first set? What about the second set?

Michael Albanese
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Answer is 3 , Sum of each set is equal to 100 so in the last set if we add 3 the sum becomes 100

Jagadeesh Kumar
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