Verbal Reasoning - Mental Ability Questions

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. 

- There are 8 letters in the word.

- The coded word can be obtained by taking the immediately following letters of word, expect the first and the last letters of the given word but in the reverse order. That means, in the coded form the first and the last letters have been interchanged while the remaining letters are coded by taking their immediate next letters in the reverse order.