Is the integer n a prime number?

Question

(1) 24  \leq  n  \leq  28
(2) n is not divisible by 2 or 3

OG Q 2017 New Question(Book Question: 218)

hsbinfy · Answer

A

1)none of the numbers 24,25,26,27,28 are prime.so suff

2) there are many numbers not divisible by 2 or 3 foe e.g. 55 or 7(former is not prime latter is)

stonecold · Answer

Great Official Question
Here we need to find whether the concern integer n is prime or not
Statement 1
 =n
n=> 24=> divisible by 2
n=> 25=> divisible by 5
n=26 => divisible by 2
n=27 => divisible by 3 
n=28 => divisible by 2
hence n is never prime 
Hence Sufficient

Statement 2
n=5
n=25
taking the above two test cases we can discard the statement.
P.S=> This statement is just saying that 2 and 3 are not prime factors of n.

Hence A

Salsanousi · Answer

None of the integers in statement 1) are prime

24 is divisible by 2
25 is divisible by 5
26 is divisible by 2
27 is divisible by 3
28 is divisible by 2

We get a sufficient answer that n is not prime.

Statement 2)

Well 5 is a prime and not divisible by neither 2 nor 3

25 is not a prime and is not divisible by neither 2 nor 3.

Insufficient.

Answer choice A

Basshead · Answer

Is the integer n a prime number?

(1) 24  \leq  n  \leq  28

n can be 24, 25, 26, 27, 28. None of these numbers are prime. SUFFICIENT.

(2) n is not divisible by 2 or 3

n could be prime or not prime. For example, n could be 7 (prime) or 55 (not prime)

ScottTargetTestPrep · Answer

Solution:

Question Stem Analysis:

We need to determine whether integer n is a prime number.

Statement One Alone:

We see that n could be 24, 25, 26, 27, or 28. Since none of these numbers are prime, the answer to the question is no. Statement one alone is sufficient.

Statement Two Alone:
 
Statement two alone is not sufficient. For example, if n = 5, then n is a prime. However, if n = 35, then n is not a prime. Statement two alone is not sufficient.

Answer: A

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Is the integer n a prime number?

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Is the integer n a prime number?

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