Unusual Math logic brain teaser

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1 + 4 = 5
2 + 5 = 12
3 + 6 = 21
8 + 11 = ?

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SherlockHolmes Expert Asked on 14th September 2016 in Puzzles.
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  • 6 Answer(s)
    Best answer

    96

    1*(4+1)=5
    2*(5+1)=12
    3*(6+1)=21
    8*(11+1)=96

    dyj Expert Answered on 14th September 2016.
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    92

    (1*4)+1=5
    (2*5)+2=12
    (3*6)+3=21
    (8*11)+4=92

    teja592 Scholar Answered on 9th October 2016.
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    1+4=5
    5+2+5=12
    12+3+6=21
    21+8+11=40

    Gmk Curious Answered on 15th September 2016.

    Each equation is independent of previous result, Only Position of equation in the series matters. hence, answer will be 96 as given by dyj

    on 16th September 2016.
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    1+(4*1)=5
    2+(5*2)=12
    3+(6*3)=21
    8+(11+8)=96

    Poornima Starter Answered on 22nd November 2016.
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    I solved this a longer way with addition.
    Answer = NUM1+NUM2+PREVIOUS SUM
    OR  sn =  x+y+ s(n-1)

    1+4 + 0 = 5
    2+5+ 5=12
    3+6+12=21
    4+7+21=32
    5+8+32=45

    8+11+77=96

    Above answers are obviously better, but I chimed in anyways

    AliceJ Starter Answered on 1st December 2016.
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    Found a bit of a unique solution to this one it seems

    1 + 4 = 5 (base 6)
    2 + 5 = 12 (base 5)
    3 + 6 = 21 (base 4)
    8 + 11 =  201 (base 3)

    Omega2227 Starter Answered on 13th April 2017.
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