P is the brother of Q and R. S is R's
mother. T is P's father. Which of the following statements cannot be definitely
true ?

Option (D)

P, Q, R are children of same parents. So, S who is R's mother and T, who is P'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.

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The present age of three brothers are in proportion 3:4:5. After five years , the sum of their ages 75. Find their ages after 5 years (in years).

Let the present ages be 3x,4x and 5x years respectively.

Then, (3x+5)+(4x+5)+(5x+5)=75

12x=60

x=5

So, after five years their ages 20 years,25 years, 30 years respectively.

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In following questions, a sequence of groups of alphabets and numbers is provided with one term missing , Choose the missing term from options. J2Z, K4X, 17V, ?, H16R, M22P

The first letters in odd numbered terms from series J, I, H and in even numbered terms from the series K, L, M. The sequence followed by the numbers is + 2, + 3, + 4, + 5, + 6. The third letter of each term is moved two steps backward to obtain the third letter of the next term.

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For a motor boat that cover A certain distance downstream in 2 hours and return 3 hours what would be its speed in still water if the speed of stream is equal 6 km per hour?

Speed of boat in still water=y[(t1+t2)/(t1_t2)]km/hr

Speed of boat in still water=x=6[(3+2)/(3-2)]=30 km/hr

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A. P. C. D. E and F are six members of a family.

One couple has parents and their children in the family.

A is the son of C and E is the daughter of A.

D is the daughter of F who is the mother of E.

What lationship do D and E bear to each other?

E is an daughter of A and F is the mother of E. So A is the father of E and hence the husband of F. Now, D is the daughter of F. So, D and E are the daughters of A and F. Also,A is the son of C. Now, only B remains. Thus, B and C are the parents of A. Clearly, D and E are sisters..

In following questions, one term in number series is incorrect.

Find out the incorrect number

11, 5, 20, 12, 40, 26, 74, 54

Find out the incorrect number

11, 5, 20, 12, 40, 26, 74, 54

The given sequence is a combination of two series:

I. 11, 20, 40, 74 and

II. 5, 12, 26, 54

The pattern in I becomes + 9, + 18, + 36, ... if 40 is replaced by 38.

So, 40 is wrong..

Peter introduces David as the son of the only brother of his father's wife.

How is Peter related to David?

The relation may be analyed as follows:

Father's wife........ Mother

Mother's brother.....Uncle

Uncle's son ........ Cousin

So, David is Peter's uncle.

So option no. 1 is correct.