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# more prime thoughts

### #1

Posted 24 September 2007 - 02:40 AM

Which of the even prime numbers [excluding 2] are [evenly] divisible by 5?

[1] all

[2] some

[3] none

[4] the question has no defensible answer.

p.s. Martini: I assert this is a logical not mathematical question.

Edited for "clarity". [meaning that I originally screwed up what I wanted to ask .. ]

I do not choose [4].

*Vidi vici veni.*

### #2

Posted 24 September 2007 - 03:17 AM

### #3

Posted 24 September 2007 - 05:47 AM

All of them. There is only one, which is 2. All other even numbers are divisible by 2 and therefore not prime. The question doesn't specify that the solution must be evenly divisible by 5, therefore ALL numbers are divisible by five, including 2.

Hmmmm.. well, ok.

But I've edited the question now, hopefully asking what I had intended to ask.

See if your answer changes ...

*Vidi vici veni.*

### #4

Posted 24 September 2007 - 06:14 AM

### #5

Posted 24 September 2007 - 01:01 PM

The set of even prime numbers excluding 2 is an empty set. Being an empty set, it simultaneously meets the criteria that all, some and none of its members are divisible by 5.

However, since answers are being chosen and reasons for those answers are being given, then by definition, there are defensible answers to the questions. Thus [4] would be incorrect.

### #6

Posted 25 September 2007 - 10:37 AM

In fairness, tho, I have changed my mind as to which answer[s] I would defend.

Today, these clues; tomorrow, my picks.

[1] Existential import.

[2] Boolean logic - as opposed to Aristotelian logic.

*Vidi vici veni.*

### #7

Posted 26 September 2007 - 06:45 AM

*Vidi vici veni.*

### #8

Posted 27 September 2007 - 12:23 AM

There you have it!

### #9

Posted 27 September 2007 - 08:01 AM

If your choice is [3], it's correct; but ...All even numbers [excluding 2] are evenly divisable by 2, and therefor not prime. Therefor there are NO EVEN PRIME NUMBERS if 2 is excluded. Hence no even prime numbers which would be evenly divisable by 5!

There you have it!

Why is it the

**best**answer?

Why did you pick it over [1]

**All**even prime numbers [excluding 2] are divisible by 5?

Aren't they

**all**divisible by 5? Show me one that is not.

[red text edited]

*Vidi vici veni.*

### #10

Posted 28 September 2007 - 05:40 AM

1. there's no even prime numbers excludeing 2. so, the solution set is none {}.

2. "evenly" is the x^2/sizeof(x). however, the size of x is zero.

It's just like customers never visit the resturant, you can't tell which one of them love the food or not.

PS. If you choose 4, it works for your spoiler, too.

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