Verbal Reasoning - Mental Ability Questions

Let 'x' be the number of new Rs.2000 notes.

Given for one new 2000 note there are three old 500 notes.

i.e, 3x

Given 10 more new Rs.2000 notes are added to the collection
and the ratio of new Rs.2000 notes to old Rs.500 notes 

x+103x=12⇒x=20

Therefore, number of new Rs.2000 notes =  x+10 = 30.

old Rs.500 notes = 3x = 60.

Thus, the total number of notes in the collection  = 30 + 60 = 90.

The numbers in the first row form a series 1², 2², 3².
So, missing number in the first row = 4² = 16.
The number in the second row from the series, 1, 2, 3, 4.
The number in the third row from the series 2, 4, 6.
So, missing number in the third row = 6 + 2 = 8.

The first letters of the terms are alternate.
The sequence followed by the numbers is +2, +3, +4,....
The last letter of is three steps ahead of the last letter of the preceding term.

Man's son's sister---Man's daughter.
So, the man's daughter is the mother of the woman's husband. Thus, the woman's husband is the grandson of the man in the photograph.

If we assign numerical value to each letter, i.e  A = 1, B = 2, C = 3 ....., each of the group shows the following relationship. 1st letter x 2nd letter = 3rd letter

According to Pradeep : 20,21 or 22...(1)
According to his brother : not 22....(2)
From (1)&(2), the birthday falls on February 20 or 21.

Clearly, when the letters of a Word are written in reverse order, the position of the middle letter remains unchanged.

Thus, in the word SELFRIGHTEOUSNESS, the middle letter it T does not change its position when the letters are reversed.