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\( p\),\( q\) and r are prime numbers. Such that p< q

A) 1
B) 2
C) 3
D) None of these

Correct Answer:


B) 2

Description for Correct answer:
2, 3, 5, 7, 11

For r=5, q=3,p=2

So p + q + r = 10 (not a prime number)

For r=7,q=5,r=3

P + q + r = 15 (not a prime number)

For r=7,q=5,r=2

=14 (not a prime number)

For r=7,q=3,r=2

P + q + r = 7 + 3 + 2

= 12 (not a prime number)

For r=11, q=7, r = 5

p + q + r = 23 (a prime number)

For r=11,q=5,r=3

p + q + r = 19 (prime number)

Hence for two cases p + q + r is prime number.

Option (B)is correct.

Part of solved CDS Maths(1) questions and answers : Exams >> CDSE >> CDS Maths(1)

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