Verbal Reasoning - Mental Ability Questions

Find out the positions of both the letters from the left and divide the sum of the positions of both the letters from the left by 2. Here 13+23=36. Now divide 36 by 2 , i.e 18. Hence R is the required letter.

first letter A with last letter Z
similarly 2nd last letter Y with 2nd letter B
Now 3rd letter C with 3rd last letter X
4th last letter W with 4th letter D
and so on....

Therefore the missing letter is X

ten = 3(number of letters)
nine = 4(number of letters)
sixty = 5(number of letters)
ninety = 6(number of letters)
seventy = 7(number of letters)
sixtysix = 8(number of letters)
ninetysix=96(number of letters)

Then, likwise choose the number which has 9 letters in its Spelling.

All cities belong to port cities of India.

Fourth to the right of the tenth from the right means (10 - 4 = )6th from the right, ie 5. But according to the queswtion, one is subtracted from each of the numbers, ie 4. 

C is wife of B. So, one couple is BC. Now, D in grandmother of A, B is the son of D and his wife C is the mother of F. SO, D is also the grandmother of F But F is the granddaughter of E. 

So, E is the grandfather of F and the husband of D. Thus, DF is another couple