Just dial spot is 1020. Just dial oct future is 1010 and nov future is 1000. I want to sell oct future is 1010 and buy Nov future is 1000 and want to hold till expiry 29 of oct. Kindly suggest

I want to know what are chances that stock future of Nov month trade at discount on the day of expiry of this month oct series. ie 29 oct, 2015

Yes you can do this. For you to make money the spread which is -10 right now has to increase. if Oct future goes 1030 and Nov to 1025, you will make Rs 5 profit. If Nov goes to 1030 and oct is at 1020 on expiry, you make 20 point profit.

That said, there is no guarantee that on the expiry day, 29th oct, Nov fut has to be more than oct fut. The difference could even become -20.