The some of any two consecutive prime numbers is also prime. True of False?

2017-09-25 10:15 pm

回答 (6)

2017-09-25 10:19 pm
False.

For example, 3 and 5 are two consecutive prime numbers.
3 + 5 = 8, where 8 is not a prime number.
2017-09-25 10:18 pm
False -- if only for the fact that each of those numbers would be odd and the addition of two odd numbers is even and therefore divisible by two.
2017-09-25 10:25 pm
True, as the only two consecutive prime numbers are "2" and "3". (Noting that "1" is NOT a prime number).

2 + 3 = 5

Five is a prime number.

All prime numbers greater than "2" are odd numbers, so cannot be consecutive; the difference between them must be at least two.
2017-09-25 11:01 pm
False

Note you are asked about any two consecutive prime numbers
NOT any two consecutive numbers that happen to be prime.

eg 7 + 11 = 18 not a prime number.

As prime numbers above 2 are always odd, and two odds make an even, the result won't be prime.
2017-09-26 1:59 am
2 is prime
7 is prime
2 + 7 = 9_______which is not prime

Thus statement is false.
2017-09-25 11:00 pm
False, 7 and 11 is 4


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