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2023 Sep 11, 12:07pm   3,403 views  50 comments

by komputodo   ➕follow (1)   💰tip   ignore  

this puzzle was on facebook...about 1300 people gave the answer and i think they were all wrong. They do not tell you the correct answer so I decided to see what you guys say. Nobody gave the same answer that i did.

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29   komputodo   2023 Sep 11, 10:13pm  

richwicks says

komputodo says



how can it be 19? By that reasoning, a+b+c+d+b+c+d+c+d+d would equal 6666 but it doesn't...It equals 51.


Would you prefer the question to be:


  A 1000 + B 100 + C 10 + D
+ B
100 + C 10 + D
+ C
10 + D
+ D
-------------------------------
6 1000 + 6 100 + 6 * 10 + 6


Then: "what is A+B+C+D?"

That's the real question. I think. It is poorly worded, and it has two solutions, and if I used normal mathematical notation, that's not the question, and if I use normal mathematical notation, there is no solution, at least for integers and if I don't use integers, there's an infinite number of solutions.

I think the question is just fine how it is written. It just seems to me that people are trying to overcomplicate it and that they have forgotten elementary school math.
30   richwicks   2023 Sep 11, 10:15pm  

komputodo says


I think the question is just fine how it is written. It just seems to me that people are trying to overcomplicate it and that they have forgotten elementary school math.


Show your work.

Maybe I am entirely misunderstanding the question.

Oh - I think I see the problem - where do you come up with this equation:

a+b+c+d+b+c+d+c+d+d

? I think that's where the discrepancy lies, and also, I don't agree this is a well worded question, because it has 2 solutions.
31   komputodo   2023 Sep 11, 10:27pm  

richwicks says


Oh - I think I see the problem - where do you come up with this equation:

a+b+c+d+b+c+d+c+d+d

?

to simplify, lets do

its not 2+4+4...its 24 + 4


32   komputodo   2023 Sep 11, 10:38pm  

richwicks says

I don't agree this is a well worded question, because it has 2 solutions.

I didn't see where it stated that there was only 1 solution
33   komputodo   2023 Sep 11, 10:48pm  

richwicks says

You must have misunderstood the question. It's asking:

ABCD +
 BCD +
  CD +
   D
----
6666

in my mind abcd = 6319 meaning a=6000, b=300, c=10 , d=9...bcd = 319, cd=19, d=9....total 6666
34   SunnyvaleCA   2023 Sep 11, 11:16pm  

richwicks says

SunnyvaleCA - that Python?

Yes python. However, the asterisk symbol, designating multiplication in Phython, is treated as toggling bold text on and off due to the HTML "markdown" feature. I really am liking python for small tasks: very straightforward syntax, lots of examples out there on the internet, and fantastic built-in and 3rd party libraries.

As an example of 3rd party libraries... My girlfriend had a 500 page book with the binding cut off and a self-feeding scanner that produced PDF scans but only 1-sided. She wanted a single PDF with all the pages in order. I had her scan all the pages using the automatic sheet feeder, flip the stack upside down and scan them all again. By the time that was done I had a python script that used a free 3rd party PDF utilities library to reverse the second set of pages and then interleve them with the first set. Done!
35   SunnyvaleCA   2023 Sep 11, 11:18pm  

stereotomy says

It's one equation with three unknowns. By the most elementary principles of linear algebra, this is a singular matrix, which necessarily has no unique solution.

Actually, it's 4 unknowns, but yeah. There are an infinite number of solutions except for the fact that you are constrained to integers between 1 and 9. That happens to limit it to 2 solutions.
36   SunnyvaleCA   2023 Sep 11, 11:20pm  

Onvacation says

That's cheating! You're supposed to do it in your head!

I'm working smarter, not harder.
37   Misc   2023 Sep 11, 11:30pm  

I believe everyone is overthinking it.

A=6000
B= 300
C= 20
D= 1.5

Answer:6321.5

Yep, I'll put $ on it.
38   SunnyvaleCA   2023 Sep 12, 1:16am  

Nobody said we needed to use base 10. How about bases 7 through 16. (Has to be at least base 7 because otherwise you can't write 6666 as the answer.

digits = "0123456789ABCDEF"
for base in range(6,16+1):
for a,b,c,d in itertools.product(range(0,base),repeat=4):
if a*base**3+b*base**2+c*base+d + b*base**2+c*base+d + c*base+d + d == (((6*base+6)*base+6)*base+6):
print(base,
, digits[a],digits[b],digits[c],digits[d],
,a+b+c+d)

7 6 2 6 5 19
10 5 8 1 9 23
10 6 3 1 9 19
11 5 8 5 7 25
13 6 2 A 8 26
14 5 9 B 5 30
14 5 A 1 C 28
14 6 2 B 5 24
14 6 3 1 C 22

Interpreting the last line of output as an example: in base 14, the numbers for a,b,c,d are 6,3,1,C and the sum of those is 22 (in base 10).
39   SunnyvaleCA   2023 Sep 12, 1:17am  

^^^ the "pre" tag worked great. I also searched for * and replaced with * .
40   richwicks   2023 Sep 12, 2:34am  

komputodo says


richwicks says


Oh - I think I see the problem - where do you come up with this equation:

a+b+c+d+b+c+d+c+d+d

?

to simplify, lets do

its not 2+4+4...its 24 + 4





yes, and 2+4 = 6

It's adding the digit of each column together. What number do you think it ought to be?
41   richwicks   2023 Sep 12, 2:38am  

SunnyvaleCA says

Yes python. However, the asterisk symbol, designating multiplication in Phython, is treated as toggling bold text on and off due to the HTML "markdown" feature.


Yeah, you can write the symbol (once) by escaping out the ascii character sequence in html, but when you go to edit it, it turns into the ascii symbol. If you really want me to demonstrate it, ask because I have to escape out symbols to demonstrate, and I'm just up in the middle of the night for a few minutes.
42   komputodo   2023 Sep 12, 12:53pm  

richwicks says

komputodo says



richwicks says



Oh - I think I see the problem - where do you come up with this equation:

a+b+c+d+b+c+d+c+d+d

?

to simplify, lets do

its not 2+4+4...its 24 + 4






yes, and 2+4 = 6

It's adding the digit of each column together. What number do you think it ought to be?

I think the reason that we disagree is because when I see a number like 24, i think of it as 20+4 and you think of it as a 2 and a 4...when i saw the number 6666, I saw 6 thousand, 6 hundred and sixty six. and you saw 4 sixes
43   richwicks   2023 Sep 12, 1:52pm  

komputodo says

richwicks says


komputodo says




richwicks says




Oh - I think I see the problem - where do you come up with this equation:

a+b+c+d+b+c+d+c+d+d

?

to simplify, lets do

its not 2+4+4...its 24 + 4







yes, and 2+4 = 6

It's adding the digit of each column together. What number do you think it ought to be?


I think the reason that we disagree is because when I see a number like 24, i think of it as 20+4 and you think of it as a 2 and a 4...when i saw the number 6666, I saw 6 thousand, 6 hundred and sixty six. and you saw 4 sixes


??


   A
+ BA
----
  28

What is A+B?


What would your answer be in this case? Show your work. I don't understand what you don't understand.
44   komputodo   2023 Sep 12, 8:28pm  

richwicks says

I think the reason that we disagree is because when I see a number like 24, i think of it as 20+4 and you think of it as a 2 and a 4...when i saw the number 6666, I saw 6 thousand, 6 hundred and sixty six. and you saw 4 sixes

??

   ``A
+ BA
-------
  28

What is A+B?

What would your answer be in this case? Show your work. I don't understand what you don't understand.
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I see it as 24...if B is 2x10 and a is 4x1, then is B=2 or B=20?
46   richwicks   2023 Sep 12, 8:48pm  

komputodo says


I see it as 24...if B is 2x10 and a is 4x1, then is B=2 or B=20?


B = 2. Just 2. It's not 20, it's not 2x10, it's just a digit between 0 and 9, and in this case, it's 2
47   komputodo   2023 Sep 12, 8:54pm  

richwicks says

komputodo says



I see it as 24...if B is 2x10 and a is 4x1, then is B=2 or B=20?


B = 2. Just 2. It's not 20, it's not 2x10, it's just a digit between 0 and 9, and in this case, it's 2

so 6666 is not 6 thousand, six hundred and sixty six? its just 4 sixes in a row?
48   richwicks   2023 Sep 12, 9:15pm  

komputodo says

richwicks says


komputodo says




I see it as 24...if B is 2x10 and a is 4x1, then is B=2 or B=20?


B = 2. Just 2. It's not 20, it's not 2x10, it's just a digit between 0 and 9, and in this case, it's 2


so 6666 is not 6 thousand, six hundred and sixty six? its just 4 sixes in a row?


A is a single digit between 0 and 9
B is a single digit between 0 and 9
same with C and D

6666 is 6 thousands, size under and sixty six. But if you were to write "6666 = WXYZ", W=6, X=6, Y=6, Z=6.
49   UkraineIsTotallyFucked   2024 Apr 25, 10:18am  

What's the answer:


50   HeadSet   2024 Apr 25, 11:00am  

UkraineIsTotallyFucked says

What's the answer:




It is either 1 or 25, most likely 1. I see that each section multiplied by the 5 in the middle equal the number on the opposite side.

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