In a can filled with solution, percentage of water is 25%. When 15 liter mixture is taken out and replaced with water new percentage of water in mixture becomes 40%. Find the capacity of can in liters. विलयन से भरे एक केन में पानी 25% है। जब 15 लीटर मिश्रण निकाला जाता है और पानी के साथ प्रतिस्थापित किया जाता है तो मिश्रण में पानी का नया प्रतिशत 40% हो जाता है। केन की क्षमता लीटर में ज्ञात कीजिये।

Let can capacity be x liters. Initially: 25% water = 0.25x, 75% solution = 0.75x. After removing 15L (which has 25% water): water removed = 15 × 0.25 = 3.75L, solution removed = 15 × 0.75 = 11.25L. Remaining water = 0.25x - 3.75, remaining solution = 0.75x - 11.25. After adding 15L water: new water = (0.25x - 3.75 + 15) = 0.25x + 11.25. This equals 40% of x: 0.25x + 11.25 = 0.4x, so 0.15x = 11.25, x = 75 liters.