# Pop Quiz, Hot Shot: Can You Solve This IQ Question?

Submitted by: fancylad 10 months ago in
12

No way am I going to post the answer here (not like I have it, but I'm positive Google will spoil the fun. Honor system -- if you know the answer, give let's hear it, and show your work.

Here's how you did with last week's pop quiz with the tanks of water.
12
6
20.  Every human knows that 8 + 12 = 20 in base 10.  Translate for any other base from 9 and on up as appropriate and as you see fit.  The middle two are just wrong as everyone knows and there to throw you off.
Male 1,871
This equation is the solution to (? + underpants = profit)
Male 1,415
Why did they think this one was so hard???  Mental midgets????
Male 1
No - the answer is 108.    1x4 +1 = 5;  2x5+2 = 12;  3x6+3 = 21; 8x12+8 = 108
In other words, there is more than one correct answer
Male 1,415
kras, 8 * 12 = 96.  then 96 + 8 = 104.
Male 6,153
8x12+8 = 104 not 108
Male 2,150
The answer is 41. The sum of the 2 numbers plus the total of the line prior. No prob, took about a minute...Gonna have to do better than that to defeat the power of pot on a snow day.
Male 6
I agree with you on all conditions
Male 6,153
If the answer to Life the Universe and Everything is 42 and the Question for that answer is what do you get when you multiply 6 by 9 is true; then 7+7 must equal 11.
Female 27
41
Male 5,167
104,  4x1+1, 5x2+2,6x3+3,12x8+8
Male 525
Male 169
If we focus on just finding solutions then all of the answers here would be valid.
Here's my take on this
• But i think there's something odd about the values on the left hand side for the fourth row.
• Consider the values on the left for the first three rows.
• Each of the row that follows has +1 added to both of its operands.
• Keeping that in mind the fourth row should be "4 + 7". But its "8+12". If there were a 8th row it would have to be "8+11".
• If we deduce an answer for the fourth row based on observations derived from the first three rows then all the answers would be incorrect.
This is just an observation. It may be true or complete crap. Just think about it.
3
I agree i commented on the odd last line when i got 56, but not sure why they are different.
Male 6,153
I noticed that too that it should read 8+11=x
the series  logic seems to be 1+4; 2+5; 3+6; 4+7; 5+8; 6+9; 7+10;8+11... but the last line is given as 8+12=X so maybe there is an aspect to the formula to determine the B in the equation A+Ba=X that people are missing

Male 4,099
I'm going to go with the answer being 104. Obviously, the riddle is not asking what is really 8 + 12, if was, the previous sums would be 5,7,9, something in the equation must be hidden or changed to us. Yet looking at the pattern if we except the first addend and the sum as always being the correct digits and the plus to instead be a multiplication sign, then the true second addend is always viewed after being subtracted by one. If that is the case, the correct way to view it is 1x5=5, 2x6=12, and 3x7=21. Therefore, if we follow the same pattern, we should view the equation in question as 8x13=?. If that is the case then the answer is 104.
Male 141
41 = (21) + (8 + 12)
Male 4,945
The I-A-B Brain Trust: Elsewhere, I-A-B'ers are posting dik-dik and beaver pics--but we're hard at work.

Male 6,153
but no wet pussy pics
Male 10
32.
Male 4,945
All right, for those keeping score, we have found four valid answers and six winners.

• 41. Total from expression before equal sign is added to expression after equal sign from previous line (using 0 for the 1st line). Credit: cobrakiller. (Falselife, you didn't show your work, which was Fancy's stipulation.)
• 104. (1st number x 2nd number) + 1st number. Credits: SAMSONMOLLY or agurney (can't tell who was first). Alternate methodology: Add 1 to the 2nd number and multiply by the 1st. Credit: Dead-Kittens.
• 56. Multiply the 2nd number by 1, then 2, then 3, then 4, ascending as you go down, then add to 1st number. Credit: andrew mann.
• 62. Expressions after the equal sign are given in bases 6, 5, 4, and 3, in descending order.  Credit: broizfam.
Male 6,077
Actually, I've been thinking about my answer and it can't be right. In base 3 what we write as 3 is written as 10. Just as we write 100 for ten 10's in base 10, three 3's is written as 100 in base 3. That means the answer to the last problem, expressed in base 3, would be 202. Shit.
Male 4,945
Waitaminnit. I'm trying to understand this and I have to step myself through it. As I figure it,  the base-10 number 20 (8 + 12) expressed in base-3 would be ... yes, 202 (2*9 + 0*3 + 2*1). You got it. Meh, that's OK. I still think you get a prize because you identified the pattern of descending bases, which was impressive. So far as I could see online, no one else came up with that. So go you!
Male 1,252
is this one of those things with multiple answers?  seems pretty simple to me ..add 1 to the second value. 8 x 13 = 104.
Male 1,252
Male 6,077
62
Male 6,077
1st is in base 6: 1+4=5
2nd is in base 5: 2+5    5 in base 5 is written as 10 and then there's 2 left over: 10+2=12
3rd is in base 4: 3+6     4 in base 4 is written as 10. There are 2 of them so it's 20 with 1 left over: 20+1=21
If I'm correct then the next one should now be down to base 3:   8+12    3 in base 3 is written as 10. There are 6 3s so that gives 60 with 2 left over:    60+2=62
Male 4,945
That also works, but I think an easier way to explain it is that the expressions before the equal signs are in base 10 and the expressions after the equal sign are given in bases 6, 5, 4, and 3, in descending order. Clever!
Male 1
I just added up all the numbers except the answers written... voila 41
Male 6,153
Given  if 6x9=42
7+7 = X
Solve for X (hint it is NOT 14)
Male 6,153
1+4(x1)=5, 2+5(x2)=12, 3+6(x3)=21,8+12(x8)=104 ,9+13(x9)=117...
Male 8,547
Your parenthesis are surperflous.  A simple 2x5+2 or 2+5x2 would suffice as the precedence of operation gives you the right answer.
Male 6,153
I used those to indicate hidden aspects of the equation
Male 8,547
was hoping you'd point  out how few people recall (or even recognize) the precedence of operation.
Male 40,764
Possibly, but you add an extra equation and that offends Occam's Razor...
-1
Male 6,153
Just continuing the series to demonstrate the logics of the sequence :-)
Male 43
104
1x4=4, 4+1=5
2x5=10, 10+2=12
3x6=18, 18+3=21
8x12=96, 96+8=104
Male 80
THE answer is 42. This is the answer to this puzzle, and to everything else.
Male 6,153
only if the question is what do you get if you multiply 6 by 9
here is another question based on that therom  if 6x9=42 what is 7+7?
Male 569
So 42 hookers and 42 grams of blow in answer to the question, "how many hookers and how much blow should I get?"
Male 80
But my alternate answer was 41.
Male 80
Or... 797.

1+4=5   →  14-5=A
2+5=12 →  25-12=B
3+6=21 →  36-21=C
8+12=? →  812-?=D

A=9, B=13, C=15, D=??

Since B-A=2*2, and C-B=2*1, we must have D-C=2*0, so D=C=15

812-?=15 → ?=812-15=797

So the final answer to the puzzle is 797.

By accepting any rule, we can get any answer we like.
3
I got 56. If you times the second number by 1, then 2, then 3 then 4, rising in order as you go down, then add them together it gives you
1 + (4x1)= 5
2 + (5x2)=12
3 + (6x3)=21
8 + (12x4)=56

not sure why the last numbers jump though from 3 to 8 and 6 to 12 though?

Male 4,945
That is really clever. Looks like we now have three valid solutions. Welcome to I-A-B, btw!
3
cheers, on here a lot but never posted before. Was quite happy with my solution though so i thought i would post it. there had better be a good official answer.
Male 7,934
This better be 41. If not I'll be totally fooled.
Male 859
104 doesn't work for me, 41 does.  In both cases, its not a proper question/puzzle.  As for the damn tanks of water, the video answer is incorrect: tank 3 fills up first, just before tank 4.
Male 4,945
41, I think. And I didn't cheat. You take the answer to the front part of the problem and add it to the incorrect answer given on the line above. So for the last line, it's: 8 + 12 + 21 = 41. Haven't looked into why people are saying 104 yet....

Hmmm. 41 works, but it means the first line serves only to prime the pump, so to speak. All in all, I think I prefer MeGrendel's solution because it works for every line of numbers. Good job, MeGrendel.

UPDATE: So a couple follow-up thoughts. First, after checking around online, the two solutions presented in this thread are both considered valid and have erupted into a kind of white & gold/blue & black dress contoversy. Second, I'm actually starting to prefer my 41 answer for the following reason. Of the two solutions, it's the only one requiring that the puzzle begin the way it does: 1 + 4 = 5. Why? Because contrary to my original thinking, it isn't there just to prime the pump: It works with no antecedent, thus: 1 + 4 + zero (because there's no preceding line) = 5. It's the only line in the puzzle where the equation makes sense as read because it's the only line with no preceding line. That suggests to me that the creator of the puzzle was using the method that produces the answer 41. I wish I could say I was smart enough to have seen both solutions, and then preferred the 41 on the grounds given above, but that's not the case. 41 was just the answer the popped out at me.
Male 569
41
Male 1,743
I saw this one a while back, I think there are a few ways to do this one:

a + b = a x b + a
1 + 4 = 1 x 4 + 1 = 5
2 + 5 = 2 x 5 + 2 = 12
3 + 6 = 3 x 6 + 3 = 21
8 + 12 = 8 x 12 + 8 = 104

a + b = a + b + previous answer
1 + 4 = 1 + 4 + 0 = 5
2 + 5 = 2 + 5 + 5 = 12
3 + 6 = 3 + 6 + 12 = 21
8 + 12 = 8 + 12 + 21 = 41

a + b = a x (b+1)
1 + 4 = 1 x (4 + 1) = 5
2 + 5 = 2 x (5 + 1) = 12
3 + 6 = 3 x (6 + 1) = 21
8 + 12 = 8 x (12 + 1) = 104

Haha, I just realized that the first one and the last one are the same. Of course. Algebra! OK, I'm done.
Male 7,833
Simple, you take the answer for each line and add it to the answer from the previous line.  so the answer is 41.

1+4=5
2+5=7         +5=12
3+6=9        +12=21
8+12=20     +21=41
Male 1,415
a mathemetician would object to them using the "=" sign though
Male 1,415
i agree with Megrendel, its 104.  3*6 + 3 =21, 8*12 + 8 = 104
Male 20,916
I'm seeing a lot of different numbers. I'm not going to say anything though because I don't know maths.
Male 40,764
(1+4) = 5 (first line)
(1+4) + (2+5) = 12 (second line)
(1+4) + (2+5) + (3+6) = 21 (third line)
(1+4) + (2+5) + (3+6) + (8+12) = 41 the answer.
I have no idea why it goes 1,2,3, 8... or 5,7,9, 20...but that's a different question :-p

-1
Male 8,547

# 104

Male 40,764
41, E-Z :-)
Male 20,916
Sorry 5cats, you didn't show your work. Zero on your daily report card.
Male 40,764
Oops, my maths ended up up there ^^ Lolz!
-1
Male 4,152
We are The Sheliak Corporate. Stop sending us gibberish.

Male 84
104.
(1st number x 2nd number) + 1st number

Edit: I made the assumption that "8 + 12 + ?" was just another i-am-bored typo that should have been "8 + 12 = ?"

Male 20,916
Thanks, Agurney -- fixed.
Male 44
You beat me to the post!
Male 1
41. Pretty simple. It's just a few "+"'s short.

Male 44
The answer is 104, I think.   1+4=5 or (1x4)+1=5 : 2+5=12 or (2x5)+2=12 : 3+6=21 or (3x6)+3=21 : so 8+12=104 or (8x12)+8=104
Please let me know if I am a "hotshot".

Male 16
Simply replace the + sign , make it a X sign , do the math then add the first number to the product. And no , I did not look at the reply's troll bastards. 8X12 = 96 +8 = 104. Not that hard at all folks.