### Brain Teasers

# A Prime (Number) Problem

There is a number that fulfills all of the following criteria/rules:

1. It is prime.

2. It is a whole number.

3. It is greater than or equal to 1.

4. If you double it, square it, and add itself to it, you get the same single digit even number answer for each operation.

What is this number?

1. It is prime.

2. It is a whole number.

3. It is greater than or equal to 1.

4. If you double it, square it, and add itself to it, you get the same single digit even number answer for each operation.

What is this number?

### Hint

The "single digit even number" mentioned in the 4th criterion/rule is equal to the number of criteria that the "mystery number" fulfills.### Answer

2.2 is prime.

2 is a whole number.

2 is greater than 1.

2 x 2 = 4.

2 ^ 2 = 4.

2 + 2 = 4.

4 is a single digit even number, and is the answer for all the above operations.

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## Comments

too easy...

N*N=N^2

N*N=N^N

Therefore, N=2.

N*N=N^N

Therefore, N=2.

Erm... I made a mistake on above comment. It said square. (What was I thinking?) I meant to say:

N*2=N+N

N*N=N+N

Therefore, N=2

N*2=N+N

N*N=N+N

Therefore, N=2

I wasn't planning on making it difficult, just exploiting a little mathematical "quirk".

it wuz pretty easy but it wuz nice to kno (:

easy but nice one!

Doubling a number is the same as adding the number to itself. Therefore, the 4th criterion is redundant.

I'm perfectly aware that the 4th criterion is redundant.

TOOK me a minute but i got it

we took that one in KG lol , just type " the only even prime number "

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