General Discussion
Related: Editorials & Other Articles, Issue Forums, Alliance Forums, Region ForumsSolve if you are genius
Be careful when answering. Agent Steve is watching.
enlightenment
(8,830 posts)got it wrong twice. I quit.
cherokeeprogressive
(24,853 posts)Zorra
(27,670 posts)Ron Green
(9,822 posts)longship
(40,416 posts)customerserviceguy
(25,183 posts)I'm sure many people get thrown by the equal sign
Nimajneb Nilknarf
(319 posts)kentuck
(111,051 posts)ZombieHorde
(29,047 posts)I'm no genius.
Capt.Rocky300
(1,005 posts)Happyhippychick
(8,379 posts)X_Digger
(18,585 posts)bemildred
(90,061 posts)Series: 2 6 12 20 30 42 56 72
Differences: 2 4 6 8 10 12 14 16
X * ( X+1 ) works too, as noted before.
Cronus Protagonist
(15,574 posts)Looks like they skipped one in the sequence to throw us off.
9=72
8=56
7=42 *puff*
6=30
5=20
4=12
3=6
2=2
1=0
0=0
end program
kentuck
(111,051 posts)It was a trick question that required closer observation.
Aerows
(39,961 posts)Yay me.
BainsBane
(53,012 posts)You don't need to be a genius. I'm innumerate. The answer is 9.
liberal N proud
(60,332 posts)Aerows
(39,961 posts)It's a regressive logic puzzle. The answer is 6.
Xipe Totec
(43,888 posts)LittleBlue
(10,362 posts)Genius?
If the number on the left is X, the number on the right is X^2 - X
Not sure about the equals sign, that's not appropriate
fried eggs
(910 posts)I got 6 too, but my logic was that the number on the left was being multiplied by 8,7,6,5,... but your approach is superior because it works even if people don't realize that the left side skips from 5 to 3.
LittleBlue
(10,362 posts)Did take a lot of math that I never used, though
Checked and someone did it up the page but factored the X out
x^2 -x = x (x-1)
demwing
(16,916 posts)Last edited Wed Sep 25, 2013, 06:27 AM - Edit history (1)
3(3-1)=6
(3^2)=6
Same stuff...
Mr_Calculus
(2 posts)f(x)=x^2-x; or: f(x)= x-1) are correct...in that both get you to the correct answer.
BUT, f(x)=x^2-x is the absolutely correct response!
NoGOPZone
(2,971 posts)reflexive property
tiny elvis
(979 posts)NoGOPZone
(2,971 posts)tiny elvis
(979 posts)it does not matter if the first five equations are wrong
are you genius?
Capt.Rocky300
(1,005 posts)Lady Freedom Returns
(14,120 posts)9=72 (56 +16)
8=56 (42+ 14)
7=42 (20+12)
5=20 (12+8)
4=12 (6+6)
3=6
cbayer
(146,218 posts)catnhatnh
(8,976 posts)onehandle
(51,122 posts)tiny elvis
(979 posts)Calista241
(5,585 posts)But I'm a math idiot. So probably wrong.
catnhatnh
(8,976 posts)that it?
truebluegreen
(9,033 posts)TheCowsCameHome
(40,167 posts)sequential 8 7 6 5 4 ...... 3
Aerows
(39,961 posts)since 3 is a prime number and you can't divide anything by it. It's a trick question, but mathematically the answer is 6 but there are about 5 different ways to make it work. You can look at it as a regressive formula, or also as simple addition and subtraction.
DCBob
(24,689 posts)9*8=72
8*7=56
7*6=42
6*5=30
5*4=20
4*3=12
3*2=6
easy.
LuvNewcastle
(16,834 posts)Looks like there's other ways people found to figure it out, too. I think our way is easiest.
DCBob
(24,689 posts)I wonder what does that mean.. if anything.
Also look here.. the poster may not have the answer.
http://www.democraticunderground.com/10022968160#post87
ugh.
LuvNewcastle
(16,834 posts)dimbear
(6,271 posts)Simplifies math a good bit.
Shankapotomus
(4,840 posts)9 (*8) = 72
8 (*7) = 56
7 (*6) = 42
6 (*5) = 30
5 (*4) = 20
4 (*3) = 12
3 *2 = 6
And who is Agent Steve? Has Agent Mike been replaced?
ThomThom
(1,486 posts)Mikes out getting high on someone else's smoke
You think he could hang out here and not get fucked-up
Earth_First
(14,910 posts)Please pick up the polling device located on the seat back of the chair in front of you and select your answer...
alphafemale
(18,497 posts)9 x 9 - 9
8 x 8 - 8
etc
HiPointDem
(20,729 posts)Uzair
(241 posts)Where is my prize?
Buns_of_Fire
(17,148 posts)Tuesday Afternoon
(56,912 posts)or bacon
truebluegreen
(9,033 posts)JVS
(61,935 posts)First of all, they're trying to trick you by saying 9=72, 8=56 and so on into order for you to recognize a pattern n=n*(n-1). But that isn't how the equality relationship works. n=n for all n. They know that people will over think it and interpret it as a congruence relationship. But that isn't technically what they wrote.
Then they're also trying to trick you by skipping from 5 to 4, so that you get out of sequence and answer 9 instead of 6.
GiveMeFreedom
(976 posts)Jamastiene
(38,187 posts)I got it wrong the first time I saw it because I didn't notice the 4 was missing.
cherokeeprogressive
(24,853 posts)Uzair
(241 posts)The answer is 24.
Buns_of_Fire
(17,148 posts)Lordy, I'm SO confused now...
Tx4obama
(36,974 posts)10 = 90
9 = 72 then (+18 = 90)
8 = 56 then (+16 = 72)
7 = 42 then (+14 = 56)
6 = 30 then (+12 = 42)
5 = 20 then (+10 = 30)
4 = 12 then (+8 = 20)
3 = 6 then (+6 = 12)
2 = 2 then (+4 = 6)
1 = 0 then (+2 = 2)
Read from the bottom up
Tuesday Afternoon
(56,912 posts)I think I see a pattern
and I love Calvin
might be a poet even
hack89
(39,171 posts)IDemo
(16,926 posts)It could be 6 if you assume the formula is X * (X-1)
It would equal null if it's X * the numeral below X (there is none below 3, not even zero)
Not sure where folks are getting 9.
geckosfeet
(9,644 posts)But I agree - there is some ambiguity.
Jamastiene
(38,187 posts)I made the same mistake on FB early this morning when I first woke up. That'll teach me to try to do weird FB math first thing in the morning.
stevenleser
(32,886 posts)stevenleser
(32,886 posts)Formula could also be (Previous value of x) -(x+x)
So
8=56
7=42 or 56-(7+7)
6=30 or 42-(6+6)
5=20 or 30-(5+5)
3=14 or 20-(3+3)
muriel_volestrangler
(101,262 posts)Tx4obama
(36,974 posts)9 = 72 (9 x 8 = 72)
3 = 21 (3 x 7 = 21)
Skip Intro
(19,768 posts)On the equals side of the list of equations, starting with 20 and going up, the difference between each starts with ten, (30-20) and increases by two.
Using that logic, if we move down from 20 on the same side, and figure the answer is the difference between 20 and 8, we end up with 12.
Maybe there's more than one answer, but that's one.
CanonRay
(14,080 posts)I got there a different way, but same answer.
geckosfeet
(9,644 posts)9x8=72
8x7=56
7x6=42 (Yay Arthur Dent)
6x5=30
5x4=20
4x3=12
3x2=6
liberal_at_heart
(12,081 posts)That's what I get for trying to do it in my head. I cannot do math in my head. I always have to write it down.
frogmarch
(12,153 posts)Skittles
(153,111 posts)what's the answer?
tjwash
(8,219 posts)I like the order of operations ones that everyone forgets how to do:
1*3+1-(3+8*3)-4=??
reformist2
(9,841 posts)IDemo
(16,926 posts)It's labeled as a math quiz but violates the rules. 3 equals 3, always.
Jamastiene
(38,187 posts)3=3 Period
All those others equal themselves with no x or other value added behind the original number.
muriel_volestrangler
(101,262 posts)The repeated use of "x=x+1" will drive you mad.
IDemo
(16,926 posts)In code, "x=x+1" uses a single equals sign as an assignment operator, meaning the right side is evaluated and the resulting value then assigned to the left side. But the expression x=x+1 will never be true in arithmetic. You can do that with a programming variable, but you can't arbitrarily make 9 = 72 in math; it's an invalid operation.
Essentially the only relevant part of the so-called "math" quiz is the last line: 3 = ??, where the answer is obviously 3. Everything above that point is meaningless. If they want to call 3.14 = cherry pie, they can call it a puzzle or riddle.
muriel_volestrangler
(101,262 posts)A quiz is not a formal examination; it doesn't mean that what appears in it must be something you could write in a mathematical paper. Quizzes can include puzzles.
If you really want to say that the answer must be something that is equal to the '3' on the left of the equals sign, then there are an infinite number of 'correct' solutions; 4-1, 25-22, -1 * -3, the real cube root of 27, etc. Which are all more interesting than putting '3' there.
IDemo
(16,926 posts)As I said, 9 will never equal 72, even in extremely large cases of 9. And yes, you can enter anything on the right-hand side of the equals sign that evaluates to the value on the left. That doesn't change my point.
muriel_volestrangler
(101,262 posts)You consider the given relations, and use knowledge of mathematical operations like multiplication and subtraction to find the pattern.
Your answer is tediously pedantic and uninteresting; and not as funny as another literal answer to a math problem:
xocet
(3,871 posts)that (integer) 3 is an equivalence class - (m,n) where m-n = 3.
If every different expression that is equal to three is allowed as an answer, what type of infinity is being discussed? Countable, Uncountable, ... ?
Do you happen to know the answer? Off hand, I don't, but it seems like a countable infinity would be too small...
muriel_volestrangler
(101,262 posts)and which convinced me I shouldn't try to study it at university, so I'm afraid I can't help you there. But since there are many (infinite?) operations as well as infinite numbers you can put into the numbers, perhaps it is uncountable.
djean111
(14,255 posts)Just a simple progression, 7x8, 6x7, 5x6, etc.
kristopher
(29,798 posts)14+(2x3)=20
20+(2X5)=30
30+(2x6)=42
42+(2x7)=56
56+(2x8)=72
muriel_volestrangler
(101,262 posts)You've calculated the '72' from all the numbers on the left below it, but ignored the '9' entirely. Not as elegant as just using the number on the left of each '=' to get the number on the right (ie the 'n=n(n-1)' formula most have used), I think.
kristopher
(29,798 posts)There is no 4 in the pattern. You can infer it, but strictly speaking without it the other answers lack symmetry. This is a code, and the "=" does not have the same function as it would in a math equation.
ETA: Forgot to address the 9. That is only used to continue the pattern to 10=90.
72+(2X9)=90
muriel_volestrangler
(101,262 posts)so a '4=12' line is unnecessary. I agree that it's a code, and '=' does not have the function it would in an equation; but, in fact, by putting it in your form, you make it less of a code. If it's a code, we can say "the '=' sign means 'multiplied by the number one less than itself is'". Your interpretation means you have to use each number on the right in 2 statements.
kristopher
(29,798 posts)But you also do not need to place a gap in the sequence. Also, your answer could be obtained with confidence from only 2 samples.
Yes it means you have to use the number in two statements - that is what turns it into a definitive pattern.
kristopher
(29,798 posts)If this were to be used in a code, remember that the idea is to disguise the information. The sender and receiver have the key, but those possibly intercepting the code must derive the meaning without the cipher.
Which answer accomplishes that?
muriel_volestrangler
(101,262 posts)Think, for instance, of ASCII - American Standard Code for Information Interchange. A cipher is always meant to disguise.
kristopher
(29,798 posts)Like many problems, it isn't defined well enough to have a single unambiguous answer. I maintain, however, that 14 is the most symmetrical solution.
sofa king
(10,857 posts)4 * 3 = 12
3 * 2 = 6
Hahaha. My first guess is always wrong.
morningfog
(18,115 posts)Taken further, 2=2, 1=0.
RedCappedBandit
(5,514 posts)immoderate
(20,885 posts)--imm
SidDithers
(44,228 posts)Sid
dipsydoodle
(42,239 posts)What's with the genius bit ?
Uzair
(241 posts)If the numbers on the left side of each equal sign progressed from 9 to 3, as in 9,8,7,6,5,4,3, this answer wouldn't work. However, they "skip" the 4 because the sequence 8,7,6,5 ends at 5. That's why that sequence is colored BLUE. The pattern in the BLUE sequence of numbers is what everybody in this thread is saying: left number "equals" left number minus 1 multiplied by left number.
Also, those who are saying that the equals sign is always an equals sign and therefore "3=3" is the answer are missing the point that every single other "equation" evaluates to "false". If you want to be logical about it, then, you would say your answer is 3 "equals" anything OTHER than 3.
Now, the red "equations" are an entirely different sequence. That's why they're colored red. There is NO REASON to color the "3=??" one red other than to distinguish it from the fact that it is completely UNREALTED to the blue ones and paired up with the only OTHER red one: The "9=72" one. Coloring "3=??" red makes it clear that there is no "skipping" of the 4.
Thus we only have two "equations" to work with.
9=72
3=??
The only relationship between numbers that we have to work with are 9 and 72,
Now 9 times 8 equals 72.
Therefore 3 times 8 equals 24.
But why multiply by 8? Because if we're going to assume that this is a sequence with some kind of logic behind it, then this makes both of these terms, namely term 3 and term 9, related only with whatever relationship we can find between 9 and 3. The relationship between 9 and 3 must also agree with our previous answer, though, when applied to the number 72.
Notice that 9 divided by 3 equals 3: Therefore 72 divided by 3 equals 24. Again, we arrive at 24.
QED.
fried eggs
(910 posts)but I don't think the graphic provides enough information to solve the problem. Every answer requires making assumptions that are not explicitly stated. 6 assumes the author left out the 4 to trick us; 9 assumes the author didn't intend for the left side to follow a sequence; and 24 assumes the colors are intentionally different. So I guess we'll never really know. lol
Tx4obama
(36,974 posts)DCBob
(24,689 posts)or was this just entirely a game?
Fun regardless...
hughee99
(16,113 posts)The only difference being that the for the red equations, the answer on the left is the sum of the digits on the right?
9=72 (9=7+2)
3=21 (3=2+1)
I guess this solution would also leave the question, though, of why wouldn't "12" be a correct answer
If this problem is asking people to look for patterns and apply them to find an answer, a number of different patters can be found leading to a number of different answers without more information.
Tikki
(14,549 posts)red descending from the blue pattern above...just a thought.
Tikki
Uzair
(241 posts)Tikki
(14,549 posts)Tikki
Tx4obama
(36,974 posts)hughee99
(16,113 posts)I see we both came up with different reasons too.
Uzair
(241 posts)My solution is found in two different ways with no ambiguity.
If the pattern is "sum of the digits", then you're lead to an ambiguous solution. It can be EITHER 12 or 21, there's no way to know. The same thing goes for people saying it's 6 or 9, "depending on"... If you have an ambiguous solution, you don't have the solution.
muriel_volestrangler
(101,262 posts)than the straightforward '6' answer? And that it's "found in two different ways"?
hughee99
(16,113 posts)All I have to do is assume the larger number comes first. 7-2 and 2-1. Now it's not ambiguous anymore.
sibelian
(7,804 posts)I think you're quite good at this sort of thing.
Response to Uzair (Reply #86)
NoGOPZone This message was self-deleted by its author.
cherokeeprogressive
(24,853 posts)Rowdyboy
(22,057 posts)Thanks
LostOne4Ever
(9,286 posts)to life, the universe, and everything was already disclosed by Douglas Adams as 42.
Therefore 7 is the question.
As for the pattern? 6.
Ligyron
(7,615 posts)Coyotl
(15,262 posts).
Demo_Chris
(6,234 posts)liberal_at_heart
(12,081 posts)burnodo
(2,017 posts)should be 6
Egalitarian Thug
(12,448 posts)Petrushka
(3,709 posts)4 = 12
3 = 6
pansypoo53219
(20,952 posts)lob1
(3,820 posts)Recursion
(56,582 posts)If the invisible functor is stateful, it could be anything, though 9 is attractive.
If it's stateless, it's 6.
If there is no invisible functor and the sentences at the top are false, it's 3
socialist_n_TN
(11,481 posts)I'd say 6. All of these numbers on the right side are the product of the number on the left multiplied by the next number down, i.e., 9x8=72, 8x7=56, etc.) Ergo, the last one would be 3x2=6. So the answer would be 6.
krispos42
(49,445 posts)4 should be 12, 3 should be 6
MineralMan
(146,248 posts)differentiated by having the same, different color. I use the red formula, which is x*8=y and arrive at 24 as the answer. Were it not for the color difference, I would assume the series x*(x-1) = y and say 6.
But, due to the color difference, 9 and 3 are marked as not part of the series. The missing 4=12 further indicates that it is not the series we are looking at but the red colored numbers.
However, since the equation itself is invalid as presented, I would be annoyed at the question and would refuse to answer, which is the correct answer, really.
On Error Resume Next
If color = red Then y = x*(x-1)
Elseif color = blue Then y = x*8
Endif
End
Tikki
(14,549 posts):}
Tikki
MineralMan
(146,248 posts)RudynJack
(1,044 posts)I got 6.
9x8
7x6
6x5
5x4
3x2 = 6
TYY
WinkyDink
(51,311 posts)The missing one is:
4 = 12. (4X3)
shawn703
(2,702 posts)Looks to be x * (x-1) for each number.
Phillip McCleod
(1,837 posts).. but this is not a math quiz.
Dead giveaway?
9 Does not equal 72. Ever. If it was a math quiz you'd use the function map arrow.
davekriss
(4,615 posts)tblue37
(65,215 posts)ON EDIT: Because the product in each of these equations is always the answer you get when you multiply the multiplicand by a multiplier that is one less than itself:
a x (a-1) = b
3 x (3-1) = 6
TreasonousBastard
(43,049 posts)recognize this as one of those tests which doesn't look for a correct answer, but for your approach to an answer. Dunno if people are still using this stuff in job interviews, but it is interesting.
"5=20" is meaningless except as a definition, and we're not told what is being defined and where the definition is being used. It could e part of some odd computer code where that sort of identity is common but usually using more sensible variables.
So, I jumped on 6, simplistically using the x-1 thing and that is one acceptable answer. However, it is simplistic and obvious and those of us using it are on the low end. Others, coming up with other rational and more elegant solutions are also "correct" but show more creativity in their answers.
If I were using this as a hiring tool, I'd put those who answered "6" in one "acceptable" pile, but some of the other answers might go into the "callback" pile.
(While fully understanding, however, that brilliant flights of fancy often get in the way of actually doing the job.)
Response to fried eggs (Original post)
u4ic This message was self-deleted by its author.
denbot
(9,898 posts)Did he view one too many kitty videos, and go all granola on the bureau?
Atman
(31,464 posts)aquart
(69,014 posts)VOX
(22,976 posts)The sequencing does not specify if the differing colors of red and blue have any bearing on the actual calculation. If not, the answer would be 6...but that can't be said for certain.
If color does matter, 24 would be a reasonable guess, if the "invisible" value 8
in the single other red equation of 9 [x8] =72 applies to all other red equations. But that's unknown as well -- there are only two red equations visible -- not enough info to establish any pattern...the answer to 3=??? could really be anything.
Dash87
(3,220 posts)demwing
(16,916 posts)1(*0)=0
2(*1)=2
3(*2)=6
4(*3)=12
5(*4)=20
6(*5)=30
7(*6)=42
8(*7)=56
9(*8)=72
10(*9)=90
etc
11 Bravo
(23,925 posts)gbloncourt
(1 post)We have to consider each line number...
number x 3+number x line# =....
Line 5: 9*3+9*5 = 72
Line 4: 8*3+8*4 = 56
Line 3: 7*3+7*3 = 42
Line 2: 6*3+6*2 = 30
Line 1: 5*3+5*1 = 20
Line 0: 3*3+3*0 = 9
NRaleighLiberal
(60,006 posts)cyberswede
(26,117 posts)But I'm definitely no genius.
Tuesday Afternoon
(56,912 posts)Mr_Calculus
(2 posts)It is actually an equation, f(x)=x^2-x (x squared minus x) ; or, if factored-out: f(x)= x-1)
ALL of the pattern suggestions are WRONG!
The correct answer, like it, or not, is: 6
f(8)=8*8-8=56
f(7)=7*7-7=42
f(6)=6*6-6=30
f(5)=5*5-5=20
f(3)=3*3-3=6
It is NOT that this took a "genius", it's more than one had to go back and re-visit how to generate an equation for ALGEBRA!
You're welcome!