### Brain Teasers

# Triples

Series
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

2 5 10

3 10 20

4 17 34

5 __ __

_ 37 __

_ __ 100

### Answer

2 5 103 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

Very easy, but I like it. Cool teaser.

Good teaser swaffy!

good brain exercise for the tougher ones

Quite a simple one!

very easy

Easy for you guys. Not so easy for me. Obviously not one of my favorites. Sorry.

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

Monday

I totally got that one!!! Need more coffee...

This is what I'm talking about! The perfect teaser. Thank you very much! 10

THIS out of all of my other teasers got Teaser of the Day?

What has the world come to?

What has the world come to?

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!

Thanks Anyway! Keep sending em

in! I might get smarter again after the Holidays! Ho! Ho! Ho!

Brain is worn out

too!

I really, really enjoyed that one!

I usually give up on this kind of teaser pretty quickly, but figured this one out and really enjoyed it. Thanks!

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.

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.

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.

Sorry, misread the directions for etcbeatty, that does work.

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.

Good one ... thank you!

I like logic puzzles and I like math puzzles ... this one combines the two.

I like logic puzzles and I like math puzzles ... this one combines the two.

Even though I solved it somewhat quickly, it was a most enjoyable 90 seconds! Thanks for submitting.

great teaser... couldnt figure it out though... maybe next time

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!

I agree it would have been a bit more challenging had it not been just the numbers 2-7 like that. However I found other people's comments interesting about other patterns they found. Very good!

Fun and easy (don't think I don't like easy ones too!)

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.

Aw well. Like I say, not bad.

Nice, easy, and fun

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

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

I got the answers but did it the same way that robert_lewis200 did...fun teaser!

Really easy, not a challenge , but fun.

enjoyed it. Thank you.

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.

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.

Got it- Reminds me of a high school IQ test question.

I am with those who do not care for this one. I never even try these kind.

Sorry!

Sorry!

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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