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21kaldridge21Aus

Posts: 231

new Posted: 01:28PM Apr 24, 2013

I found this on Facebook and really want to know the answer.

It said 98% will fail

2 = 6
3 = 12
4 = 20
5 = 30
6 = 42
9 = ??


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jaycr*us

Posts: 2233

new Posted: 04:47PM Apr 24, 2013

I believe 9 = 90
Look for a pattern.


It's not what you know, it's what people think you know.
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Innovative*ca

Posts: 76

new Posted: 06:51PM Apr 24, 2013

Solved it too.

Here's a hint: (Very small)

result / initial number


---This message was edited on 06:51PM Apr 24, 2013---

"This thaw took a while to thaw, it's going to take a while to unthaw." -George W. Bush, on liquidity in the markets.
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RGW4Ausmod

Posts: 1233

new Posted: 08:05PM Apr 24, 2013

I think the answer is:

72

Answer above


A person who never made a mistake never tried anything new. -Albert Einstein-
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jaycr*us

Posts: 2233

new Posted: 08:31PM Apr 24, 2013

RGW, I guess that would work too. There could be two answers. Agreed?

It's not what you know, it's what people think you know.
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RGW4Ausmod

Posts: 1233

new Posted: 10:22PM Apr 24, 2013

Jay, I am sure there could be, how did you come up with 90?

In fact, I was actually trying to figure how you came up with 90 when I saw a pattern.

What appeared to be missing was what made 2 = 6... a missing 3 times 2 = 6
The next missing number is 4 times, then 5 times... down to the last number where 8 times 9 = ?? or 72.

Edit because I had my numbers backwards, no incorrectly stated


---This message was edited on 05:33PM Apr 26, 2013---

A person who never made a mistake never tried anything new. -Albert Einstein-
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jaycr*us

Posts: 2233

new Posted: 05:51AM Apr 25, 2013

7 and 8 are missing but I kept them in the pattern for my answer. Does that make sense?

It's not what you know, it's what people think you know.
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21kaldridge21Aus

Posts: 231

new Posted: 12:04PM Apr 25, 2013

I got 90 for my answer too.

Here is how I did it
2 x 3 = 6
3 x 4 = 12
4 x 5 = 20
5 x 6 = 30
6 x 7 = 42
7 x 8 = 56
8 x 9 = 72
9 x 10 = 90

My mom also tried to figure it out and got 90 a different way.

Here is my mom did it
12 - 6 = 6
20 - 12 = 8
30 - 20 = 10
42 - 30 = 12
42 + 14 = 56
56 + 16 = 72
72 + 18 = 90

But I don't think this is right since it said 98% of people will get this wrong so if so many people are getting 90 as the answer then that can't be right.


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RGW4Ausmod

Posts: 1233

new Posted: 05:52PM Apr 25, 2013

Interesting way of solving the puzzle... I didn't add in two extra numbers because frankly, the way the question was put it wasn't looking for an endless sequence.

I think it's safe to say one of our answers is the "correct" one and one is wrong. Now how did the majority vote?


A person who never made a mistake never tried anything new. -Albert Einstein-
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celticherotus

Posts: 790

new Posted: 08:34PM Apr 25, 2013

I also got 90. Still don't quite get the 72 answer.

Also, kal, I think you were lied to on the Internet.


I'm just an ordinary average guy with nothing to lose.
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JQPublic

Posts: 1812

new Posted: 08:51AM Apr 26, 2013

I think Randy misread the teaser since it said 2 = 6 and not 3 = 6. Since they said 98% will fail, I think we can safely assume it isn't 90, either.

There's probably a trick in the equal sign. Has anyone heard of this one:

1 = 1
2 = 4
3 = 9
4 = ?

Answer: 2

We're assuming it's a sequence when, presented in such a manner, it may not be. What we've been doing so far is assuming f(2) = 6, and looking for f(x). What we should actually do is to think out of the box, IMO ...


---This message was edited on 08:56AM Apr 26, 2013---

'An idea, like a ghost, must be spoken to a little before it will explain itself.' - Charles Dickens
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21kaldridge21Aus

Posts: 231

new Posted: 09:09AM Apr 26, 2013

celtichero wrote:
I also got 90. Still don't quite get the 72 answer.

Also, kal, I think you were lied to on the Internet.


I think they get the 72 like this:
2 x 3 = 6
3 x 4 = 12
4 x 5 = 20
5 x 6 = 30
6 x 7 = 42
7 x 8 = 56
9 x 8 = 72

But if you look at the pattern you would know that is wrong.


---This message was edited on 09:12AM Apr 26, 2013---

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SliceOPiAus

Posts: 273

new Posted: 01:28AM Jun 26, 2013

98% will fail because they will continue to be wrong while the remaining 2% will realize that there is no correct answer and stop trying.

The life of man, solitary, poor, nasty, brutish, and short.
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Steve1973Aus

Posts: 822

new Posted: 02:21PM Jun 30, 2013

21kaldridge21 wrote:
I found this on Facebook and really want to know the answer.

It said 98% will fail

2 = 6
3 = 12
4 = 20
5 = 30
6 = 42
9 = ??


2 = 6. START
3 = previous number (6) + 1 + UP_ONE_ON_LEFT(2) + CURRENT_LEFT (3) = 12
4 = 12 + 1 + 3 + 4 = 20
5 = 20 + 1 + 4 + 5 = 30
6 = 30 + 1 + 5 + 6 = 42
9 = 42 + 1 + 6 + 9 = 58

OR
2 = 6 START
3 = PREVIOUS NUMBER (6) + 2 * CURRENT NUMBER(6) = 12
4 = 12 + 8 = 20
5 = 20 + 10 = 30
6 = 30 + 12 = 40
9 = 40 + 18 = 58

Who says we need to continue the pattern for 7 and 8? That's not the question.... 98% get it wrong, because 58 is the answer.


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Steve1973Aus

Posts: 822

new Posted: 03:08PM Jun 30, 2013

OR

2 = 6 START
3 = CURRENT NUMBER ^ 2 (9) + PREVIOUS NUMBER ON LEFT (2) + 1. = 12
4 = 16 + 3 + 1 = 20
5 = 25 + 4 + 1 = 30
6 = 36 + 5 + 1 = 42
9 = 81 + 6 + 1 = 88

Math is all about sequence manipulation of numbers. I'd say 90, 58, 88, and several more numbers could fit this pattern. Since 98% of people are supposed to get this wrong, I'd say 90 is the incorrect answer since its the obvious one. (F(n) = n ^ 2 + n)

What the correct answer is then? I guess that depends on if you're creative enough to find a working pattern that isn't in the 98%.


Like to chat? Share links? Don't want to be told, it's a No-No to do so? Then come join us in THE REAL GENERAL DISCUSSION talkbox -- where you can post with only the lightest of moderation.
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MDCTeaserscus

Posts: 1828

new Posted: 12:02AM Apr 8, 2014

I came up with 90.

1 = 4
2 = 6
3 = 12
4 = 20
5 = 30
6 = 42
7 = 56
8 = 72
9 = 90

I added 1, 7, and 8. But: here's how it makes sense. IGNORE THE FIRST NUMBERS. And... add 2 to 4. What is the sum? 6. Keep adding 2 to the number you added before. So...

4+2=6
(**adding previous sum=2)2+4=6**
6+6=12
(*adding 2+previous add)2+6=8*
12+8=20
8+2=10*
10+20=30
10+2=12*
30+12=42
12+2=14*
42+14=56
14+2=16*
56+16=72
16+2=18*
72+18=90

Now look at the bold numbers and... surprise!!! They match the answers! So that's MY method... but probably I'm one of the 98% wrong. Or maybe they meant 98% are right? Anyway, please everyone share their methods and answers (which most will probably be 90)!


When things matter, you can be sure there is dark matter or Dark Jedi around.
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