Which one of the following is a prime number ?

551 > 22

All prime numbers less than 24 are : 2, 3, 5, 7, 11, 13, 17, 19, 23.

119 is divisible by 7; 187 is divisible by 11; 247 is divisible by 13 and 551 is divisible by 19.

So, none of the given numbers is prime.

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The ages of two friends Julie is twice older than Katie. However if the age of Julie before 20 years and that of Katie after 20 years then Katie age is twice then Julie. What is the age of julie?

let, Julie age = A and Katie age=B

given that

A/B = 2 / 1

A=2B

A - 2B = 0......equation 1

and also given that, A - 20 / B+ 20 = 1/2

2A -40 = B + 20

2A-B= 60.....equation 2

by solving watch equation

A = 40

so, julie is 40 years old

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A family consists of 6 members P, Q, R, S, T, and U . There are two married couples . Q is a doctor and the father of T ,U is grandfather of R and is a contractor . s is grandmother of T and is a housewife. There is one doctor, one contractor -one house wife and two students in the family.

Which of the following is definitely a group of male members?

Q the doctor, is the father of T. S, the house wife, is the grandmother of T and hence the mother of Q. Since there are only two married couples one being that of Q, the grandfather of R i. e, U must be married to S. Thus, R and T will be both children of Q and these must be the student. So P, who remains, Shell be the wife of Q and she alone can be the nurse. Thus, U must be the contractor. Clearly, for definite the males are Q, the father and U, the grandfather..

These are six persons A ,B, C, D , E,and F is a sister of F. B is a brother of E's husband. D is the father of A and grandfather of F. There are two fathers, three brothers and a mother in the group. Who is the mother?

D is father of A and grandfather of F. So, A is father of F. Thus, D and A are the two fathers. C is the sister of F. So, C is the daughter of A . Since there is only one mother, it is evident that E is the wife of A and hence the mother of C and C and F. So, B is brother of A . There are three brothers. So, F is the brother of C. Clearly, E is the mother..