Subject: General Aptitude · Chapter: Number System · Exam: 2008 · Marks: · Difficulty:
Which of the following is a prime number?
(a)115
(b)119
(c)127
(d)None of these
Answer
Answer (as printed): C
Explanation
We know that 115 is divisible by 5. So, it is not prime. 119 is divisible by 7 . So, it is not prime. $127<(12)^{2}$ and prime numbers less than 12 are 2, 3, 5, 7, 11. Clearly, 127 is not exactly divisible by any of them. Hence, 127 is a prime number.
Explanation as extracted from the printed page; notation may be imperfect.