tricks and shortcuts for alphabetical quibble

Hi

  just started to prepare for exams. thought i could share some tricks and shortcuts which would be useful for those who are preparing for exam
        

1.    right + right = minus the number and count from right
2.    left + left = minus the number and count from left
3.    right + left = add the number and count from  left
4.    left + right = add the number and count from right 

Q:  A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

 1.  Which letter is seventh to the right of the eighteenth letter from the right end of the alphabet? 

  Ans : P
  to obtain the answer 18-7=11
  now count  from  right end 11th term is P
 2. Which letter is seventh to the right of the thirteenth letter from the left end?
   Ans : T
   here add 7 and 13 = 20
   count  from left end 20th term is T
 all the best for your exams