Verbal Reasoning - Mental Ability Questions

P, Q, R are children of same parents. So. S who is R's mother and T, who is R's father will be mother and father of all three. 

However, it is not mentioned whether Q is male or female So, D cannot be definitely true. 

Cup is used to drink something with the help of lips. Similarly, birds collect grass with the help of beak to make her nest.

Hence, Cup : Lip :: Bird : Grass.

The given number series is 10, 6, 8, 15, ?

10

10 x 0.5 + 1 = 6

6 x 1 + 2 = 8

8 x 1.5 + 3 = 15

15 x 2 + 4 = 34

Hence, the next number in the given series is 34.

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 F. 

So, B is brother of A There are three brothers. So. F is the brother of C. 

 Clearly, A is E's Husband.

Clearly, From 1 to 100, there are ten numbers with 3 as the unit's digit - 3, 13, 23, 33, 43, 53, 63, 73, 83, 93 and ten numbers with 3 as the ten's digit - 30, 31, 32, 33, 34, 35, 36, 37, 38, 39.

So, required number = 10 + 10 = 20.