Gst rate on purchase and sale can be same or different. If different mention some cases.

Gst rate on sale and purchase are same if a person is into trading business..

Gst rate on sale and purchase are different if a person is into manufacturing business..In manufacturing business goods are procured at different rate and the resultant product may be at a different rate..

For example book publishing firm procures paper for publishing book at 5% gst but the resultant published books and periodicals are exempt in gst.