SOLUTION: why does adding 2 prime numbers or odd numbers equal an even number?

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Question 466423: why does adding 2 prime numbers or odd numbers equal an even number?
Found 2 solutions by Gogonati, solver91311:
Answer by Gogonati(855)   (Show Source): You can put this solution on YOUR website!
When you multiply by 2 the result is always even number. Assume n an odd number
then n+n=2n. 2n is divisible by 2, thus is an even number.

Answer by solver91311(24713)   (Show Source): You can put this solution on YOUR website!


Adding two prime numbers does NOT always result in an even number. 2 is prime and 3 is prime. 2 plus 3 is 5 and 5 is odd.

However, adding two odd numbers always results in an even number, so you can say that adding any two prime numbers that are GREATER THAN 2, results in an even number because all prime numbers greater than 2 are odd. They have to be because if any prime number greater than 2 was an even number, it would have a factor of 2 and wouldn't be prime.

The th odd number is . The th odd number is .



And the sum is divisible by 2 for all integers and . Any number divisible by 2 is even by definition.

John

My calculator said it, I believe it, that settles it
The Out Campaign: Scarlet Letter of Atheism


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