Note that there are 100 paise in one rupee. Let x be the number of 10 paise coins. Then the number of 25 paise coins is 3x. The number of 50 paise coins is 3x + 5 The total amount of money in the bag is 120 Rupees, which is equal to 12,000 paise. We can set up an equation. 10x + 25(3x) + 50(3x+5) = 12,000 10x + 75x + 150x + 250 = 12,000 235x = 11,750 x = 11,750 / 235 x = 50 The number of 10 paise coins in the bag is 50.