Explanation:

Revenue from Operations Rs 8,00,000; Gross Profit Ratio 25%; Opening Inventory Rs 1,00,000; Closing Inventory Rs 60,000. 

cost revenue from operations= revenue from operations - gross profit 

                                               =Rs 8,00,000 - 25%

                                                =Rs. 6,00,000

Average inventory= opening inventory = closing inventory / 2

                             =  Rs 1,00,000 +  Rs 60,000./2

                             = Rs. 80,000

inventory turnover ratio= cost of revenue from operation / average inventory

                                     = Rs. 6,00,000 / Rs. 80,000

                                      = 7.5 times