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Bunuel
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dushdan
1) the only two prime numbers which are also consecutive integers are 2 and 3. Thus, since p+1=prime p=2 p+2=2+4=6 So, we can say that p+4 is not a prime number with certainty. SUFFIcient

2) lets see two cases:
p=2 p+4=2+6=6 not prime
p=7 p+4=7+4=11 prime
Thus we cannot say with certainty that p+4 is prime INSUFFICIENT

1) would be sufficient if it said P was prime, but P can be any integer
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If p is an integer, is p + 4 a prime number less than 50?

(1) p + 1 is a prime number.
(2) p is a prime number.

Solution
(1) p=2 p+1 = 3 (prime) -> 2+4 = 6 is not prime
p=1 p+1 = 2 (prime) -> 1+4 = 5 is prime less than 50.

Not sufficient

(2) p is prime number.
p = 2 -> p+4 = 6 not prime.
p = 3 -> p+4 = 7 prime less than 50

Kudos if you appreciate my explanation.

Not sufficient.


Together:
p and p+1 are consecutive prime numbers.

Thus
p=2 and p+1 = 3

p+4 = 6 -> Not a prime less than 50.

Answer C
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