Today's brainteaser

[Nytrunner]

An odd little facebook sequential math problem has popped up gain, and today I noticed something interesting that escaped my attention before.

Have at it, no name calling

 

[kuririn]

8 + 11 = 40?
May I ask what escaped your attention?

 

[Bat-mite]

96

 

[Bat-mite]

8 + 11 = 40?
May I ask what escaped your attention?

You are incorrect, sir. 96

 

[Nytrunner]

8 + 11 = 40?
May I ask what escaped your attention?

The fact that two different sequences result in exactly the same answer. I came up with my answer rather quickly and it agrees with Bat's; however, upon reading the comments, I quickly realized others were getting my results with an entirely different sequence. A quick trip to excel revealed that both sequences are accurate with respect to each other. Must be the selection of number pairs.

My question, did you use a) addition only, or b) multiplication to get your answer

 

[Bat-mite]

1 * 4 +1 = 5
2 * 5 + 2 = 12
3 * 6 + 3 = 21
8 * 11 + 8 = 96

 

[kuririn]

Addition only, adding the correct answer to the previous total. Seems like that would also yield a "correct" answer of 40.

 

[Bat-mite]

Addition only, adding the correct answer to the previous total. Seems like that would also yield a "correct" answer of 40.

My apologies! I never would have seen that. So we'll have to split the prize.

 

[Zeus-cat]

So the + sign is clearly not an addition sign, but a stand-in for an operator that says to multiply the two numbers together and add the first digit again. Hmmm...

 

[kuririn]

Haha! If the prize is bragging rights, I shall defer to you. On the other hand, if Nytrunner has a Cosmodrome Aerobee Hi two stager in his closet...…………………………………………….

 

[Mushtang]

I'm going to go with 19 and assume that the middle two lines are there just to confuse those who want to imagine additional numbers that aren't shown. Haha.

 

[boatgeek]

Since that one was over so quickly, here's a series operation question. You have a series that uses algebraic functions to convert n = 1, 2, 3, ... into the series results. For example, the operator n*(n+1) would result in a series 2, 6, 12, 20, ...

The resultant series is 1, 2, 3, 4, 29, ... What is the operator?

 

[kuririn]

https://www.bing.com/videos/search?...1C06414A72D342FD716B1C06414A72D34&FORM=VDQVAP

 

[Nytrunner]

I'm going to go with 19 and assume that the middle two lines are there just to confuse those who want to imagine additional numbers that aren't shown. Haha.

 

[Nytrunner]

I kid (partially)

Since this is 4 lines on a piece of notebook paper, folks will make whatever assumptions are necessary to complete the data to their satisfaction. It's the assumptions and results (however flawed) that makes discussion so entertaining

Treating each line independently like Boat, you find an operator that makes sense for all cases 1,2,3, and 8. This operator involves a smidgen of multiplication to make things work and is universal regardless of whether there are "missing" lines.

Treating it as a series results using addition only, you have to incorporate the results of the last line. If you do so, you have another choice; restrict to what's on the paper, or carry the series on fully from 1-8. 1 of those choices aligns perfectly with the multiplication approach. That alignment is what I found interesting. a) totally independent lines using the same operator b) addition dependent upon previous results, => same answer

 

[Rockyt]

2 additional possibilities:

4*11 + 8 = 54 (4th problem, using similar logic to the '96' answer)

or

32 (0(answer implied)-(difference of 5)-> 5 -(difference of 7)-> 12 -(difference of 9)-> 21 - (difference of 110)-> 32 the answer is in the answers, not the questions.

 

[adrian]

Question: "What's two and two?"
Mathematician: "That's easy. Four."
Computer scientist: "No, two AND two is two. If he'd said 'two PLUS two', it would be four."
Lawyer: "For $1000, what would you like it to be?"

Since that one was over so quickly, here's a series operation question. You have a series that uses algebraic functions to convert n = 1, 2, 3, ... into the series results. For example, the operator n*(n+1) would result in a series 2, 6, 12, 20, ...

The resultant series is 1, 2, 3, 4, 29, ... What is the operator?

n + 24 * INT(ln(n)/ln(5))

 

[boatgeek]

Question: "What's two and two?"
Mathematician: "That's easy. Four."
Computer scientist: "No, two AND two is two. If he'd said 'two PLUS two', it would be four."
Lawyer: "For $1000, what would you like it to be?"
n + 24 * INT(ln(n)/ln(5))

I think lawyers charge more for the service of bending facts.

That's a creative approach that fits the pattern, though not what I was thinking. I guess I could go all Captain Technicality on whether LN and INT() are algebraic functions. The next number in my series is 126.

 

[jderimig]

These things are so bogus. + and = signs have unambiguous meanings and rules. This isn't Vietnam.

When someone answers these things on Facebook your name is added to a database of impressionable gullible people and that information is sold to those who can profit from a pool of such people.

 

[Nytrunner]

Which is why I steal them and post here so i can watch!

 

[Lugnut56]

 

[Wallace]

I saw 96, is that the true and correct answer? And no, I will not show my work because it's internal and would probably require a bone saw or some such..

 

[rharshberger]

I think lawyers charge more for the service of bending facts.

But a good statistician can make data turn out how YOU want it to be and thats priceless![emoji3]

"Figures lie, and Liars figure."

 

[neil_w]

My answer: 201.

Explanation later.

 

[boatgeek]

But a good statistician can make data turn out how YOU want it to be and thats priceless![emoji3]

"Figures lie, and Liars figure."

"There are lies, damned lies, and statistics."

One of my mom's stats classes had "How To Lie With Statistics" as a textbook. I read it much later, and it's still surprisingly relevant. It's really intended to help people identify other people lying with stats.

 

[Wallace]

An odd little facebook sequential math problem has popped up gain, and today I noticed something interesting that escaped my attention before.

Have at it, no name calling

Ya arse...

 

[cwbullet]

Yeah, no.