A shopkeeper purchased two rice bags, 'Brown Rice' and 'Basmati,' and sold them at identical prices. The bag of 'Brown Rice' was sold with a 20% profit, while the 'Basmati' bag was sold for a profit of Rs. 2925, resulting in an overall profit of 12.5% for the entire transaction. Given that the ratio of the cost price of 'Brown Rice' to that of 'Basmati' is 4:5, determine the cost price of the 'Brown Rice' bag.

ATQ, Let, the cost price of Bag 'Brown rice' be Rs. '160x'. So, the cost price of Bag 'Basmati rice' = (5/4) × 160x = Rs. '200x' So, the selling price of Bag 'Basmati' = Rs. 200x + 2925 The total cost price of both the Bags = 160x + 200x = Rs. '360x' So, the total selling price of both the Rice bags = 1.125 × 360x = Rs. '405x' Selling price of Bag 'Brown rice' = 1.2 × 160x = Rs. '192x' So, the selling price of Bag 'Basmati rice' = 405x - 192x = 200x + 2925 Or, 213x - 200x = 2925 OR, 13x = 2925 Or, x = (2925/13) So, x = 225 Let, the cost price of Bag 'Brown rice' be Rs. '160x'. So, the cost price of Bag 'Basmati' = (5/4) × 160x = Rs. '200x' So, the selling price of Bag 'Basmati' = Rs. 200x + 2925 The total cost price of both the Bags = 160x + 200x = Rs. '360x' So, the total selling price of both the Bags = 1.125 × 360x = Rs. '405x' Selling price of Bag 'Brown rice' = 1.2 × 160x = Rs. '192x' So, the selling price of Bag 'Basmati' = 405x - 192x = 200x + 2925 Or, 213x - 200x = 2925 OR, 13x = 2925 Or, x = (2925/13) So, x = 225 The cost price of Bag 'Brown rice' = 160x = 160 × 225 = Rs.36,000