Triples
Series teasers are where you try to complete the sequence of a series of letters, numbers or objects.
A Triple is a Series with 6 sets, each with 3 numbers apiece. The relationship between the first two numbers is the same throughout all of the sets, and the relationship between the last two numbers is also the same, however, it is different than the first relationship. Try and find the missing numbers:
2 5 10
3 10 20
4 17 34
5 __ __
_ 37 __
_ __ 100
Answer
2 5 10
3 10 20
4 17 34
5 26 52
6 37 74
7 50 100
Relationship for first two numbers: square it, add 1 (2 squared=4, 4+1=5)
Relationship for last two numbers: double it (5 doubled = 10)
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Comments
TheEarthling
Dec 29, 2005
 Very easy, but I like it. Cool teaser. 
froggygg
Jan 02, 2006
 Good teaser swaffy!

mr_brainiac
Jan 02, 2006
 good brain exercise for the tougher ones 
RRAMMOHAN
Dec 23, 2007
 Quite a simple one! 
doehead
Dec 23, 2007
 very easy 
bradon182001
Dec 23, 2007
 Easy for you guys. Not so easy for me. Obviously not one of my favorites. Sorry. 
mondayschild59
Dec 23, 2007
 I suck at math. I'm sorry, I didn't get it. But at least you posted and for that I am greatful. Maybe I'll do better next time.
Monday 
UptheHill
Dec 23, 2007
 I totally got that one!!! Need more coffee... 
karma48
Dec 23, 2007
 This is what I'm talking about! The perfect teaser. Thank you very much! 10 
bigSWAFF_69_
Dec 23, 2007
 THIS out of all of my other teasers got Teaser of the Day?
What has the world come to? 
2ndhandrose
Dec 23, 2007
 I Dunno. Coffee or Tea is needed!I got on one correct!
Thanks Anyway! Keep sending em
in! I might get smarter again after the Holidays! Ho! Ho! Ho!
Brain is worn out
too! 
Harmony_Girl
Dec 23, 2007
 I really, really enjoyed that one! 
karenokupniak
Dec 23, 2007
 I usually give up on this kind of teaser pretty quickly, but figured this one out and really enjoyed it. Thanks! 
(user deleted)
Dec 23, 2007
 This is one of those odd problems (that occur frequently in math) where you can come up with the right answer the wrong way. I added the first two numbers of line one and the first number of line two to obtain the middle number of line two, then doubled that for the third number in line two. This is consistent throughout. 
lordmikel
Dec 23, 2007
 4+4+5 = 13 and not 17. So that wouldn't work. I see where it worked for the first two lines, but it quickly stops.
I liked this puzzle, my only complaint, you went 2 through 7. I might've liked to have seen you jump ahead. 11, 101, something higher. 
lordmikel
Dec 23, 2007
 Sorry, misread the directions for etcbeatty, that does work. 
robert_lewis200
Dec 23, 2007
 there's other correspondences with numbers too...I got the same answers but used a different way. If you notice, the first column of numbers is 2, 3, 4, so 5 & 6 make sense. The last column is double the middle column. The numbers in the middle column differ by the odd numbers....between 2 and 5 is a difference of 3, between 10 and 3 is a difference of 7, then a difference of 9, 11, etc. 
SweetPotato
Dec 23, 2007
 Good one ... thank you!
I like logic puzzles and I like math puzzles ... this one combines the two. 
wordmama
Dec 23, 2007
 Even though I solved it somewhat quickly, it was a most enjoyable 90 seconds! Thanks for submitting. 
dogg6pound9
Dec 23, 2007
 great teaser... couldnt figure it out though... maybe next time 
glou
Dec 23, 2007
 Yeah I like these too, but also figured it out working up and down (first column just went 1, 2, 3, 4, 5, 6, 7; second column was first add 5, then 7,then 9, then 11, then 13 etc...; third column was add 10, then 14, then 18, then 22, then 24 etc....). Good one though! 
s_o_s
Dec 24, 2007
 I agree it would have been a bit more challenging had it not been just the numbers 27 like that. However I found other people's comments interesting about other patterns they found. Very good! 
wandering_goat
Dec 24, 2007
 Fun and easy (don't think I don't like easy ones too!) 
FatHead
Dec 27, 2007
 Not bad, but a little too easy because of the pattern in the first column, as etcbeatty implicitly pointed out.
Aw well. Like I say, not bad. 
Inukai
Nov 07, 2008
 Nice, easy, and fun 
stdedos
Dec 23, 2010
 Or, think it this way to complete the second column:
The number in the second column is:
Mumber of the first column plus the sum of the first and the second numbers of the previous line 
patiencewithaP
Dec 23, 2010
 I got the answers but did it the same way that robert_lewis200 did...fun teaser! 
auntiesis
Dec 23, 2010
 Really easy, not a challenge , but fun. 
here2
Dec 23, 2010
 enjoyed it. Thank you. 
menso415
Dec 23, 2010
 i got it right but if you add the first 2 numbers, thats the difference between the first two numbers of the next set.. try it. 
lukasiwicz
Dec 23, 2013
 As has been pointed out, there's more than one way to skin this cat. My point of entry was noticing that the second number in each row, divided by the first number, equals the first number plus its reciprocal ((2/5 = 2 + (1/2)), and so on. Everything else then fell into place. But the recognition that the second number in each row equals that number squared, plus one, is conceptually neater. 
Zykezex
Dec 23, 2013
 Got it Reminds me of a high school IQ test question. 
Babe
Dec 23, 2016
 I am with those who do not care for this one. I never even try these kind.
Sorry! 
Zykezex
Dec 23, 2016
 If possible to describe a teaser as "elegant" this is it; (albeit in a simplistic way). I'm reminded that life need not be complicated nor exceedingly difficult to be worth experiencing. Well done. 
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