Jump to content


Welcome to BrainDen.com - Brain Teasers Forum

Welcome to BrainDen.com - Brain Teasers Forum. Like most online communities you must register to post in our community, but don't worry this is a simple free process. To be a part of BrainDen Forums you may create a new account or sign in if you already have an account.
As a member you could start new topics, reply to others, subscribe to topics/forums to get automatic updates, get your own profile and make new friends.

Of course, you can also enjoy our collection of amazing optical illusions and cool math games.

If you like our site, you may support us by simply clicking Google "+1" or Facebook "Like" buttons at the top.
If you have a website, we would appreciate a little link to BrainDen.

Thanks and enjoy the Den :-)
Guest Message by DevFuse
 

Photo
- - - - -

Subtraction


  • This topic is locked This topic is locked
64 replies to this topic

#41 goodswill84

goodswill84

    Newbie

  • Members
  • Pip
  • 1 posts

Posted 31 March 2008 - 06:01 AM



OR JUST DIVIDE 32 BY 2 AND YOU GET 16 :P
  • 0

#42 sunshipballoons

sunshipballoons

    Junior Member

  • Members
  • PipPip
  • 47 posts

Posted 02 April 2008 - 06:04 PM

Spoiler for Solution


This answer is wrong, and I'll prove it:

32-2 = 30
32-2 = 30

There, I proved that you can subtract 2 from 32 at least twice, even using the logic of the original solution.

Wait, I can do it a third time.

32-2 = 30

and a fourth...
  • 0

#43 richmond89

richmond89

    Newbie

  • Members
  • Pip
  • 1 posts

Posted 03 April 2008 - 06:06 PM

Subtraction - Back to the River Crossing Puzzles
How many times can you subtract the number 2 from the number 32?


Spoiler for Solution


Once, because then you would be subtracting 2 from a number different than 32.

Clever ;)
  • 0

#44 brainwwings

brainwwings

    Newbie

  • Members
  • Pip
  • 8 posts

Posted 04 April 2008 - 01:07 PM

17
  • 0

#45 Theo

Theo

    Newbie

  • Members
  • Pip
  • 17 posts

Posted 10 April 2008 - 07:15 PM

This answer is wrong, and I'll prove it:

32-2 = 30
32-2 = 30

There, I proved that you can subtract 2 from 32 at least twice, even using the logic of the original solution.

Wait, I can do it a third time.

32-2 = 30

and a fourth...


The question is, "how many times can you subtract 2 from 32?" Not, how many time can you subtract 2 from 32, and 32?"

There are 2 ways I think of the number 32 in this riddle. One is thinking of the number as 2 blocks. One block with the number 3 and another with the number 2. Only one block exists with the number 2, so it only can be subtracted once.

Another is obviously mathmatical. Subtract 2 from 32 you get 30. The number 32 no longer exists and is replaced with the number 30.There is no part of the riddle that includes additional number 32's.


... i think i just sucked the fun out of this riddle.
  • 0

#46 insidexraindrops

insidexraindrops

    Newbie

  • Members
  • Pip
  • 11 posts

Posted 12 April 2008 - 02:19 PM

Although rookie1ja's answer is quite clever, in reality you could subtract 2 from 32 an infinite number of times; the answer would be a negative.
  • 0

#47 mollie

mollie

    Newbie

  • Members
  • Pip
  • 3 posts

Posted 04 May 2008 - 04:08 AM

Subtraction - Back to the River Crossing Puzzles
How many times can you subtract the number 2 from the number 32?


Spoiler for Solution


I disagree. You can subtract it as many times as you want. Watch:
32-2=30
32-2=30
32-2=30
32-2=30
32-2=30
32-2=30
That time, I felt like doing it 5 times. :P
  • 0

#48 mollie

mollie

    Newbie

  • Members
  • Pip
  • 3 posts

Posted 04 May 2008 - 04:09 AM

Whoops didn't read all the way through. I'm not the first one to comment that. Sorry, all.
  • 0

#49 rcammoore

rcammoore

    Junior Member

  • Members
  • PipPip
  • 21 posts

Posted 14 May 2008 - 07:07 PM

WARNING: the following answer is one of those "nitpicky" type answers, but I'm really just trying to inject some humor.

Several people have suggested that the answer is infinite because you can subtract 2 from 32 once (32-2 = 30), and then you can do it again (32-2=30), and then you can do it again...as many times as you want.

There's a flaw in this though - the question asks how many times YOU can subtract 2 from 32. It takes a discreet amount of time to do that calculation, although it is pretty quick. Given that the action takes a discreet amount of time, and YOU will only live for discreet amount of time, there is a limit to the number of times that YOU can subtract 2 from 32.

Assuming that a person devotes the rest of their life to doing just this:
It takes me about 2.5 seconds to say "thirty two minus two equals thirty" at a normal pace, but if you are a speed talker, or if you're doing it in your head, you can certainly do it faster. Even it's 1 second per transaction, it's unlikely that you'll live to be more than 150 years old, and anyone reading this riddle has to be at least 3 years old to actually be able to read it, so:
(150-3)years x 365.25days x 24hours x 60minutes x 60 seconds = 4,638,967,200 times.

So my answer to the question: roughly 4.5 billion times.

:)
  • 0

#50 Born to Win

Born to Win

    Newbie

  • Members
  • Pip
  • 16 posts

Posted 21 May 2008 - 03:47 PM

Only once..
32-2=30
there is no 32 now for 2 to be subtracted :P
  • 0




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users

38