Tax calculation under Goa GST amended to adopt rule seven reference, replacing prior fixed rate wording and scope. The notification substitutes the previous rate based phrase with a provision that tax shall be 'calculated at the rate specified in rule 7 of the Central Goods and Services Tax Rules, 2017', thereby aligning the State notification's tax computation wording with the methodology prescribed in the Central Rules; the amendment is effected under section 10(1) of the Goa Goods and Services Tax Act and takes effect from the Government's stated commencement date.