How to Find Term Number 'N' from Nth term Formula of Arithmetic Sequences
http://ItsMyAcademy.com/arithmetic-se... For Free Complete Video Tutorial on Sequence & Series.- Nth term of an Arithmetic Sequences = A + (N-1).D
Using this formula according to information given in the problems you can easily solve the problems and get the required N .
To find N its really easy three parts is given so you just need to find n or 4th part.