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Maths Puzzle
-1,11,39,89,167,__,__
Read Solution (Total 2)
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- -1,11,39,89,167,__,__
-1,11,39,89,167,279,431
2^3-3^2= -1
3^3-4^2= 27-16=11
..
..
6^3-7^2 = 216 -49 = 167
7^3-8^2= 343-64 = 279
8^3-9^2 = 512-81= 431 - 12 years agoHelpfull: Yes(7) No(0)
- this series can be further decomposed like this
-1,11,39,89,167_,_
11-(-1)=12
39-(11)=28
89-(39)=50
167-(89)=78
all together a new series
12,28,50,78
again decomposing in simpler form
28-12=16
50-28=22
78-50=28
now this series seems to be bit simpler
16,22,28
here we adding 6 to the preceding digit now next digit is
28+6=34
adding 34 in last series last digit that is 78
we got 78+34=112
again adding 112 in the original series we will get the answer that is
112+167=279
same procedure apply for next digit
that comes 34+6=40
adding 40 in 112=152
and adding 152in 279=431
(this is the concept of decomposition of awkward series into simpler one and work well in most of the situation ) - 12 years agoHelpfull: Yes(3) No(2)
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