Urgent: GST Billing related

wadhwanisam2@gmail.com (111 Points)

21 July 2017  
My client has a wholesale buisness of Namkeen.
Suppose he purchase a bag of namkeen @ Rs. 1000 add gst @ 12% it comes to 1120.
Then what amount he would bill for if its profit margin is Rs. 20 per bag

Whether it would bill for
i. 1120+20+12% gst.=1276.8
or
ii. 1000+20+12%gst.= 1142.4

As if it will for (i) option then it means there will be tax on tax. So pls clarify. And also clarify the sale value if it is opt for composition scheme.

Thanks in Advance.