Answers

2014-04-21T12:23:01+05:30
2014-04-21T12:25:03+05:30
Correct answer is 3.
longest chain is of 6 carbon.
Now numbering starts from that end which give less number to more prior group.
So numbering starts such that ethyl group get 3 position.
And rest you know..
1 5 1