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# Subtraction

### #41

Posted 31 March 2008 - 06:01 AM

OR JUST DIVIDE 32 BY 2 AND YOU GET 16

### #42

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...

### #43

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

### #44

Posted 04 April 2008 - 01:07 PM

### #45

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.

### #46

Posted 12 April 2008 - 02:19 PM

### #47

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.

### #48

Posted 04 May 2008 - 04:09 AM

### #49

Posted 14 May 2008 - 07:07 PM

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.

### #50

Posted 21 May 2008 - 03:47 PM

32-2=30

there is no 32 now for 2 to be subtracted

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