Subhash can copy 50 pages in 10 hours; Subhash and Prakash together can copy 300 pages in 40 hours. In how much time can Prakash copy 30 pages?

• ক 12 hours ✅ সঠিক উত্তর
• খ 11 hours
• গ 15 hours
• ঘ 18 hours