View Full Version : Brainteaser


Abi
06-18-15, 06:24 PM
Make [] + [] + [] = 30 by filling in the three boxes with numbers from the set

(1, 3, 5, 7, 9, 11, 13, 15)

You may use any of these numbers more than once. You must place one number in each of the three boxes.

Fuzzy12
06-18-15, 06:49 PM
5+7+9=30 :)

Abi
06-18-15, 06:51 PM
:lol:

Fuzzy12
06-18-15, 06:54 PM
Cmon abi..the curiosity is killing me... :eek:

Fuzzy12
06-18-15, 06:56 PM
Do the numbers have to go inside the box? Otherwise how about 1[]+1[]+1[]=30

???

Abi
06-18-15, 07:03 PM
The numbers have to go inside the box. 1 number per box.

Abi
06-18-15, 07:04 PM
Hint: try a few random combinations of the numbers given and observe the type of answers you get closely.

Greyhound1
06-18-15, 07:09 PM
Can they be negative numbers? When you say they can be used more than once, can they be used more than once and added together and put into one box? Can they be squared basically for one box?

Abi
06-18-15, 07:11 PM
Hound: None of the above is allowed.

Greyhound1
06-18-15, 07:11 PM
Hint: try a few random combinations of the numbers given and observe the type of answers you get closely.

They are always going to be odd numbers

Abi
06-18-15, 07:13 PM
And therefore? :)

Fuzzy12
06-18-15, 07:14 PM
Hint: try a few random combinations of the numbers given and observe the type of answers you get closely.

Hm.. How is it possible to get an even number with 3odd numbers? Is this a trick question? If not, do I need to know anything that wasn't taught in primary school?

Lunacie
06-18-15, 07:16 PM
Three odd numbers added together will always result in an odd number.
30 is an even number, so I don't think it's possible.:umm1:

Abi
06-18-15, 07:17 PM
It is a trick question.

You don't need anything beyond elementary arithmetic.

Abi
06-18-15, 07:19 PM
Luna is correct :) (tho Hound did a bunch of the heavy lifting)

The sum of 3 odd numbers will always be odd. I'll spare you guys the torture of seeing it proved, tho it's quite short and easy to do.

Greyhound1
06-18-15, 07:19 PM
And therefore? :)

It's futile?

Fuzzy12
06-18-15, 07:20 PM
So is the answer that it's not possible? Is there a trick answer or is the trick that you just wasted precious moments of my life trying to figure out possible trick answers? :lol:

dvdnvwls
06-18-15, 07:21 PM
11+13+6=30

I took the liberty of turning the 9 upside down before using it. :)

Abi
06-18-15, 07:21 PM
Nope, not possible. :-)

Fuzzy12
06-18-15, 07:22 PM
Yup, precious moments it is.. :mad::doh::doh::doh:

dvdnvwls
06-18-15, 08:15 PM
What if it's not base 10?

Abi
06-18-15, 08:16 PM
Nice twist.

Let's try it.

Abi
06-18-15, 08:27 PM
11 + 13 + 7 works in base 11 :-)

Abi
06-18-15, 08:28 PM
Sorry, I shouldn't call it base 11. Base B where B represents the number "eleven"

Abi
06-18-15, 08:36 PM
A more elegant one: 1 + 11 + 11 in base 3

Edit: this is wrong, sorry.

dvdnvwls
06-18-15, 08:48 PM
So, are you saying that the conventionally correct answer is the same as what the mathematician remarked on seeing a huge new statue of the number 3 on the sidewalk? :)

Abi
06-18-15, 10:25 PM
Huh??:-):-)

psychopathetic
06-18-15, 11:29 PM
Hey DVD! It's nice to see ya man! :)

psychopathetic
06-18-15, 11:33 PM
I cheated and google searched this. Would take a ******* genius to figure this one out with no hints.
Me? I don't even know wtf bases are in math! :lol:

What if it's not base 10?

Very freaking clever DVD!

dvdnvwls
06-19-15, 03:18 AM
So, are you saying that the conventionally correct answer is the same as what the mathematician remarked on seeing a huge new statue of the number 3 on the sidewalk? :)

Huh??:-):-)

He said "That's odd..." :)

stef
06-19-15, 03:23 AM
*checks what this thread is about and runs away*

BellaVita
06-19-15, 03:50 AM
*checks what this thread is about and runs away*

I hear ya, stef.

dvdnvwls
06-19-15, 04:09 AM
Me? I don't even know wtf bases are in math! :lol:

All your base are belong to us. :)

With normal numbers (called base 10), the columns multiply by 10. The normal number 101 means a one, no tens, and a hundred. With base 2, the columns multiply by 2. The base 2 number 101 means a one, no twos, and a four.

You can have base anything-you-like. When using bases of more than 10, there aren't enough digits to count as high as needed, so the digits are usually supplemented with letters. Each column in base sixteen is usually written with 1,2,3,4,5,6,7,8,9,A,B,C,D,E,F, where FB2 would mean 2 ones, eleven sixteens, and fifteen two-hundred-fifty-sixes.

The usual reason for using any of these other bases is that you're using a piece of equipment or doing a project where counting things in tens is unnatural or not helpful.

Pilgrim
06-19-15, 07:47 AM
What is this?

Little Missy
06-19-15, 08:21 AM
What is this?

An off-shoot of word problems. The bane of my elementary school existence.:scratch:

Pilgrim
06-19-15, 08:49 AM
An off-shoot of word problems. The bane of my elementary school existence.:scratch:

Right.

midnightstar
06-19-15, 05:15 PM
Make [] + [] + [] = 30 by filling in the three boxes with numbers from the set

(1, 3, 5, 7, 9, 11, 13, 15)

You may use any of these numbers more than once. You must place one number in each of the three boxes.

15 + 13 + 3 - 1 = 30

(I think) :lol:

*brain explodes*

Too many numbers :doh:

Lunacie
06-19-15, 05:59 PM
15 + 13 + 3 - 1 = 30

(I think) :lol:

*brain explodes*

Too many numbers :doh:

... tidies up the brain debris ...

http://images.clipartof.com/small/1140381-Cartoon-Of-A-Happy-Blond-Girl-Sweeping-Royalty-Free-Vector-Clipart.jpg

psychopathetic
06-19-15, 09:28 PM
All your base are belong to us. :)

With normal numbers (called base 10), the columns multiply by 10. The normal number 101 means a one, no tens, and a hundred. With base 2, the columns multiply by 2. The base 2 number 101 means a one, no twos, and a four.

You can have base anything-you-like. When using bases of more than 10, there aren't enough digits to count as high as needed, so the digits are usually supplemented with letters. Each column in base sixteen is usually written with 1,2,3,4,5,6,7,8,9,A,B,C,D,E,F, where FB2 would mean 2 ones, eleven sixteens, and fifteen two-hundred-fifty-sixes.

The usual reason for using any of these other bases is that you're using a piece of equipment or doing a project where counting things in tens is unnatural or not helpful.

Ummmmm

B?
Yes. Yes that's my final answer! I think.
?

...WAIT!
No!
LEFT!
Left is the correct answer?

:(
I want my mommy!