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Mensa Challenge

Here is a puzzle from this months Mensa bulletin:

5        2
14      20
26      ?

What is the last number?

james
Tuesday, August 03, 2004

44 ?

Procrastinator
Wednesday, August 04, 2004

17 ?

Maverick
Wednesday, August 04, 2004

Both of these suggested answers look possible, but how can one be ruled out in favor of the other?

pete
Wednesday, August 04, 2004

26?

Trottier
Saturday, August 07, 2004

I think it is 17

SUNDAR RAJAN
Monday, August 09, 2004

As a mathematician these puzzles really fuck me off. You could come up with some kind of formula or other that would fit those numbers and make the missing one anything you like. Who's to say which formula is the most 'obvious' / elegant / right one? It's a really arbitrary judgement and certainly not a valid test of IQ (but then what is?)

Matt
Saturday, August 14, 2004

Usually I can find a answer that definately seems superior to other possible answers--in this case I can not. This problem was presented as part of a google advertisement trying to induce anyone who can solve it to put in a resume with google.

James
Saturday, August 14, 2004

i think it is 17

suyog
Sunday, August 15, 2004

Could be 17, could be 32...

A.M.
Monday, August 16, 2004

I like 44.

Mack
Saturday, September 04, 2004

42. It is always the answer.

Thomas
Saturday, September 04, 2004

I like 44 as well.

_
Thursday, September 09, 2004

Hi all,

These are some of the answers(which are simple though) i could find:

26 L of the A - 26 Letters of the Alphabet

7 D of the W  -  7  Days of the Week

7 W of the W -  7 Wonders of the World

52 C in a P (WJs) - 52 Cards in a Pack (Without Jokers)

13 S in the USF - 13 stars in the United States Flag

365 D in a Y - 365 Days in a Year

52 W in a Y - 52 Weeks in a Year

60 M in a H - 60 Minutes in a Hour

64 S on a C B - 64 Squares on a Chess Board

1000 Y in a M - 1000 Years in a Millenium

12 S of the Z - 12 Signs of the Zodiac

15 P in a R T - 15 Players in a Rugby Team

11 P in a F (S) T - 12 Players in a Football (Soccer) Team

12 M in a Y - 12 Months in a Year

29 D in F in a L Y - 29 Days in February in a Leap Year

66 B of the B - 66 Books of the Bible

39 B of the O T - 39 Books of the Old Testament

27 B in the N T - 27 Books in the New Testament

18 H on a G C - 18 Holes on a Golf Course

5 T on a F - 5 Toes on a Foot

90 D in a R A - 90 Degrees in a Right Angle

3 B M (S H T R) -  3 Blind Mice (See How They Run)

32 is the T in D F at which W F - 32 is the Temparature in Degrees Fahrenheit at which Water Freezes

3 W on a T - 3 Wheels on a Tricycle

13=UFS - 13 = Unlucky For Some

8 T on a O - 8 Tentacles on a Octopus

13 L in a B D - 13 Loaves in a Baker's Dozen

9 L of a C - 9 Lives of a Cat

23 P of C in the H B - 23 Pairs of Chromosomes in the Human Body

6 B to an O in C - 6 Balls to an Over in Cricket

15 M on a D M C - 15 Men on a Dead Man's Chest

Karthikayan
Tuesday, September 14, 2004

Hard to believe nobody suggested 35.

Michael Eisenberg
Wednesday, September 15, 2004

-1

James Harlow
Monday, September 20, 2004


9

G. Harany
Friday, September 24, 2004

its 14 or 38.

the  difference between the 5 and 2 is 3.

the difference between 14 and 20 is 6.

so logically the difference between 26 and blank is 12.

since the pattern is less(2<5) than greater(20>14) and then again less(14<26)

I am betting its 14.

MRK
Wednesday, September 29, 2004

It's 17!

inandjo taurel
Monday, October 11, 2004

It's 14

gina
Wednesday, October 13, 2004

So here, I think, is a slightly more interesting challenge:

Consider the grid above.

For *each* possible value of ? in the following set, give a rule that would entail that that value is the "correct" one for ?:

{4, 7, 100, -5, pi}

(I deliberately picked a more-or-less nonsensical set of replies...but I'm pretty confident a diligent solver *could* come up with a vaguely reasonable-sounding rule for each of them.)

Avrom Roy-Faderman
Thursday, October 14, 2004

its not stars in the us flag...its stripes

Bob
Wednesday, October 20, 2004

24 Hours in a Day
26 Letters of the Alphabet
7 Days in a Week
7 Wonders of the World
12 Signs of the Zodiac
66 Books of the Bible
52 Cards in  a Pack without Jokers
13 Stripes in the United State Flag
18 Holes on a Golf Course
39 Books of the Old Testament
5 Toes on a Foot (5 Tines on a Fork)
90 Degrees in a Right Angle
3 Blind Mice (See How they Run)
32 is the temperature in Degrees Fahrenheit at which Water freezes
15 Players in a Rugby Team
3 Wheels on a Tricycle
100 Copecks in a Ruble
11 Players on a Football (Soccer) Team
12 Months in a Year
13 = Unlucky for Some
8 Tentacles on an Octopus
29 Days in February in a Leap Year
27 Books in the New Testament
365 Days in a Year
13 Loaves in a Baker's Dozen
52 Weeks in a Year
9 Lives of a Cat
60 Minutes in an Hour
23 Pairs of Chromosome in the Human Body
64 Squares on a Chess Board
9 Provinces in South Africa
6 Balls to an Over in Cricket
1000 Years in a Millenium
15 Men on a Dead Man's Chest

#071616
Wednesday, October 20, 2004

35 looks good to me?

Phil
Thursday, October 28, 2004

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